Merge branch 'rel_0_9'

Conflicts:
	lib/sqlalchemy/dialects/postgresql/hstore.py
	lib/sqlalchemy/util/__init__.py
	lib/sqlalchemy/util/compat.py

19 files changed, 171 insertions, 187 deletions

diff --git a/lib/sqlalchemy/dialects/firebird/base.py b/lib/sqlalchemy/dialects/firebird/base.py
index 95196f44c..bb60a591e 100644
--- a/lib/sqlalchemy/dialects/firebird/base.py
+++ b/lib/sqlalchemy/dialects/firebird/base.py
@@ -685,7 +685,7 @@ class FBDialect(default.DefaultDialect):
                                 self.normalize_name(row['fname']))
             fk['referred_columns'].append(
                                 self.normalize_name(row['targetfname']))
-        return fks.values()
+        return list(fks.values())
 
     @reflection.cache
     def get_indexes(self, connection, table_name, schema=None, **kw):
@@ -716,7 +716,7 @@ class FBDialect(default.DefaultDialect):
             indexrec['column_names'].append(
                                 self.normalize_name(row['field_name']))
 
-        return indexes.values()
+        return list(indexes.values())
 
     def do_execute(self, cursor, statement, parameters, context=None):
         # kinterbase does not accept a None, but wants an empty list
diff --git a/lib/sqlalchemy/dialects/informix/base.py b/lib/sqlalchemy/dialects/informix/base.py
index 77361a5d0..e13ea8819 100644
--- a/lib/sqlalchemy/dialects/informix/base.py
+++ b/lib/sqlalchemy/dialects/informix/base.py
@@ -24,6 +24,7 @@ from sqlalchemy import sql, schema, exc, pool, util
 from sqlalchemy.sql import compiler, text
 from sqlalchemy.engine import default, reflection
 from sqlalchemy import types as sqltypes
+from functools import reduce
 
 RESERVED_WORDS = set(
     ["abs", "absolute", "access", "access_method", "acos", "active", "add",
@@ -298,7 +299,7 @@ class InfoDDLCompiler(compiler.DDLCompiler):
 
     def get_column_default_string(self, column):
         if (isinstance(column.server_default, schema.DefaultClause) and
-            isinstance(column.server_default.arg, basestring)):
+            isinstance(column.server_default.arg, util.string_types)):
                 if isinstance(column.type, (sqltypes.Integer, sqltypes.Numeric)):
                     return self.sql_compiler.process(text(column.server_default.arg))
 
@@ -506,7 +507,7 @@ class InformixDialect(default.DefaultDialect):
             if remote_column not in remote_cols:
                 remote_cols.append(remote_column)
 
-        return fkeys.values()
+        return list(fkeys.values())
 
     @reflection.cache
     def get_pk_constraint(self, connection, table_name, schema=None, **kw):
diff --git a/lib/sqlalchemy/dialects/mssql/base.py b/lib/sqlalchemy/dialects/mssql/base.py
index fc952f4b5..a5d789be1 100644
--- a/lib/sqlalchemy/dialects/mssql/base.py
+++ b/lib/sqlalchemy/dialects/mssql/base.py
@@ -295,7 +295,7 @@ class _MSDate(sqltypes.Date):
         def process(value):
             if isinstance(value, datetime.datetime):
                 return value.date()
-            elif isinstance(value, basestring):
+            elif isinstance(value, util.string_types):
                 return datetime.date(*[
                         int(x or 0)
                         for x in self._reg.match(value).groups()
@@ -328,7 +328,7 @@ class TIME(sqltypes.TIME):
         def process(value):
             if isinstance(value, datetime.datetime):
                 return value.time()
-            elif isinstance(value, basestring):
+            elif isinstance(value, util.string_types):
                 return datetime.time(*[
                         int(x or 0)
                         for x in self._reg.match(value).groups()])
@@ -1008,7 +1008,7 @@ class MSDDLCompiler(compiler.DDLCompiler):
         # handle other included columns
         if index.kwargs.get("mssql_include"):
             inclusions = [index.table.c[col]
-                            if isinstance(col, basestring) else col
+                            if isinstance(col, util.string_types) else col
                           for col in index.kwargs["mssql_include"]]
 
             text += " INCLUDE (%s)" \
@@ -1109,7 +1109,7 @@ class MSDialect(default.DefaultDialect):
                  query_timeout=None,
                  use_scope_identity=True,
                  max_identifier_length=None,
-                 schema_name=u"dbo", **opts):
+                 schema_name="dbo", **opts):
         self.query_timeout = int(query_timeout or 0)
         self.schema_name = schema_name
 
@@ -1129,7 +1129,7 @@ class MSDialect(default.DefaultDialect):
 
     def initialize(self, connection):
         super(MSDialect, self).initialize(connection)
-        if self.server_version_info[0] not in range(8, 17):
+        if self.server_version_info[0] not in list(range(8, 17)):
             # FreeTDS with version 4.2 seems to report here
             # a number like "95.10.255".  Don't know what
             # that is.  So emit warning.
@@ -1156,7 +1156,7 @@ class MSDialect(default.DefaultDialect):
             try:
                 default_schema_name = connection.scalar(query, name=user_name)
                 if default_schema_name is not None:
-                    return unicode(default_schema_name)
+                    return util.text_type(default_schema_name)
             except:
                 pass
         return self.schema_name
@@ -1194,7 +1194,7 @@ class MSDialect(default.DefaultDialect):
         s = sql.select([tables.c.table_name],
             sql.and_(
                 tables.c.table_schema == owner,
-                tables.c.table_type == u'BASE TABLE'
+                tables.c.table_type == 'BASE TABLE'
             ),
             order_by=[tables.c.table_name]
         )
@@ -1208,7 +1208,7 @@ class MSDialect(default.DefaultDialect):
         s = sql.select([tables.c.table_name],
             sql.and_(
                 tables.c.table_schema == owner,
-                tables.c.table_type == u'VIEW'
+                tables.c.table_type == 'VIEW'
             ),
             order_by=[tables.c.table_name]
         )
@@ -1273,7 +1273,7 @@ class MSDialect(default.DefaultDialect):
             if row['index_id'] in indexes:
                 indexes[row['index_id']]['column_names'].append(row['name'])
 
-        return indexes.values()
+        return list(indexes.values())
 
     @reflection.cache
     @_db_plus_owner
@@ -1480,4 +1480,4 @@ class MSDialect(default.DefaultDialect):
             local_cols.append(scol)
             remote_cols.append(rcol)
 
-        return fkeys.values()
+        return list(fkeys.values())
diff --git a/lib/sqlalchemy/dialects/mssql/information_schema.py b/lib/sqlalchemy/dialects/mssql/information_schema.py
index 80e59d323..a7628f213 100644
--- a/lib/sqlalchemy/dialects/mssql/information_schema.py
+++ b/lib/sqlalchemy/dialects/mssql/information_schema.py
@@ -9,6 +9,7 @@
 from ... import Table, MetaData, Column
 from ...types import String, Unicode, Integer, TypeDecorator
 from ... import cast
+from ... import util
 
 ischema = MetaData()
 
@@ -17,10 +18,8 @@ class CoerceUnicode(TypeDecorator):
     impl = Unicode
 
     def process_bind_param(self, value, dialect):
-        # Py2K
-        if isinstance(value, str):
+        if util.py2k and isinstance(value, util.binary_type):
             value = value.decode(dialect.encoding)
-        # end Py2K
         return value
 
     def bind_expression(self, bindvalue):
diff --git a/lib/sqlalchemy/dialects/mssql/pyodbc.py b/lib/sqlalchemy/dialects/mssql/pyodbc.py
index beb6066f5..5a359d179 100644
--- a/lib/sqlalchemy/dialects/mssql/pyodbc.py
+++ b/lib/sqlalchemy/dialects/mssql/pyodbc.py
@@ -219,7 +219,7 @@ class MSExecutionContext_pyodbc(MSExecutionContext):
                     # without closing it (FreeTDS particularly)
                     row = self.cursor.fetchall()[0]
                     break
-                except self.dialect.dbapi.Error, e:
+                except self.dialect.dbapi.Error as e:
                     # no way around this - nextset() consumes the previous set
                     # so we need to just keep flipping
                     self.cursor.nextset()
diff --git a/lib/sqlalchemy/dialects/mysql/base.py b/lib/sqlalchemy/dialects/mysql/base.py
index 076fa2517..ad4650f6d 100644
--- a/lib/sqlalchemy/dialects/mysql/base.py
+++ b/lib/sqlalchemy/dialects/mysql/base.py
@@ -640,7 +640,7 @@ class BIT(sqltypes.TypeEngine):
 
         def process(value):
             if value is not None:
-                v = 0L
+                v = 0
                 for i in map(ord, value):
                     v = v << 8 | i
                 return v
@@ -1139,14 +1139,10 @@ class SET(_StringType):
             #   No ',' quoting issues- commas aren't allowed in SET values
             # The bad news:
             #   Plenty of driver inconsistencies here.
-            if isinstance(value, util.set_types):
+            if isinstance(value, set):
                 # ..some versions convert '' to an empty set
                 if not value:
                     value.add('')
-                # ..some return sets.Set, even for pythons
-                # that have __builtin__.set
-                if not isinstance(value, set):
-                    value = set(value)
                 return value
             # ...and some versions return strings
             if value is not None:
@@ -1159,7 +1155,7 @@ class SET(_StringType):
         super_convert = super(SET, self).bind_processor(dialect)
 
         def process(value):
-            if value is None or isinstance(value, (int, long, basestring)):
+            if value is None or isinstance(value, util.int_types + util.string_types):
                 pass
             else:
                 if None in value:
@@ -1340,7 +1336,7 @@ class MySQLCompiler(compiler.SQLCompiler):
           of a SELECT.
 
         """
-        if isinstance(select._distinct, basestring):
+        if isinstance(select._distinct, util.string_types):
             return select._distinct.upper() + " "
         elif select._distinct:
             return "DISTINCT "
@@ -1429,7 +1425,7 @@ class MySQLDDLCompiler(compiler.DDLCompiler):
                         MySQLDDLCompiler, self).create_table_constraints(table)
 
         engine_key = '%s_engine' % self.dialect.name
-        is_innodb = table.kwargs.has_key(engine_key) and \
+        is_innodb = engine_key in table.kwargs and \
                     table.kwargs[engine_key].lower() == 'innodb'
 
         auto_inc_column = table._autoincrement_column
@@ -2034,7 +2030,7 @@ class MySQLDialect(default.DefaultDialect):
                 have = rs.fetchone() is not None
                 rs.close()
                 return have
-            except exc.DBAPIError, e:
+            except exc.DBAPIError as e:
                 if self._extract_error_code(e.orig) == 1146:
                     return False
                 raise
@@ -2317,7 +2313,7 @@ class MySQLDialect(default.DefaultDialect):
         rp = None
         try:
             rp = connection.execute(st)
-        except exc.DBAPIError, e:
+        except exc.DBAPIError as e:
             if self._extract_error_code(e.orig) == 1146:
                 raise exc.NoSuchTableError(full_name)
             else:
@@ -2341,7 +2337,7 @@ class MySQLDialect(default.DefaultDialect):
         try:
             try:
                 rp = connection.execute(st)
-            except exc.DBAPIError, e:
+            except exc.DBAPIError as e:
                 if self._extract_error_code(e.orig) == 1146:
                     raise exc.NoSuchTableError(full_name)
                 else:
@@ -2791,11 +2787,8 @@ class _DecodingRowProxy(object):
         item = self.rowproxy[index]
         if isinstance(item, _array):
             item = item.tostring()
-        # Py2K
-        if self.charset and isinstance(item, str):
-        # end Py2K
-        # Py3K
-        #if self.charset and isinstance(item, bytes):
+
+        if self.charset and isinstance(item, util.binary_type):
             return item.decode(self.charset)
         else:
             return item
@@ -2804,11 +2797,7 @@ class _DecodingRowProxy(object):
         item = getattr(self.rowproxy, attr)
         if isinstance(item, _array):
             item = item.tostring()
-        # Py2K
-        if self.charset and isinstance(item, str):
-        # end Py2K
-        # Py3K
-        #if self.charset and isinstance(item, bytes):
+        if self.charset and isinstance(item, util.binary_type):
             return item.decode(self.charset)
         else:
             return item
diff --git a/lib/sqlalchemy/dialects/mysql/cymysql.py b/lib/sqlalchemy/dialects/mysql/cymysql.py
index 0806f63b4..deb2de449 100644
--- a/lib/sqlalchemy/dialects/mysql/cymysql.py
+++ b/lib/sqlalchemy/dialects/mysql/cymysql.py
@@ -25,15 +25,9 @@ class _cymysqlBIT(BIT):
 
         def process(value):
             if value is not None:
-                # Py2K
-                v = 0L
-                for i in map(ord, value):
+                v = 0
+                for i in util.iterbytes(value):
                     v = v << 8 | i
-                # end Py2K
-                # Py3K
-                #v = 0
-                #for i in value:
-                #    v = v << 8 | i
                 return v
             return value
         return process
diff --git a/lib/sqlalchemy/dialects/mysql/oursql.py b/lib/sqlalchemy/dialects/mysql/oursql.py
index db24adf03..77370f91d 100644
--- a/lib/sqlalchemy/dialects/mysql/oursql.py
+++ b/lib/sqlalchemy/dialects/mysql/oursql.py
@@ -55,10 +55,10 @@ class MySQLExecutionContext_oursql(MySQLExecutionContext):
 
 class MySQLDialect_oursql(MySQLDialect):
     driver = 'oursql'
-# Py2K
-    supports_unicode_binds = True
-    supports_unicode_statements = True
-# end Py2K
+
+    if util.py2k:
+        supports_unicode_binds = True
+        supports_unicode_statements = True
 
     supports_native_decimal = True
 
@@ -90,12 +90,11 @@ class MySQLDialect_oursql(MySQLDialect):
         connection.cursor().execute('BEGIN', plain_query=True)
 
     def _xa_query(self, connection, query, xid):
-# Py2K
-        arg = connection.connection._escape_string(xid)
-# end Py2K
-# Py3K
-#        charset = self._connection_charset
-#        arg = connection.connection._escape_string(xid.encode(charset)).decode(charset)
+        if util.py2k:
+            arg = connection.connection._escape_string(xid)
+        else:
+            charset = self._connection_charset
+            arg = connection.connection._escape_string(xid.encode(charset)).decode(charset)
         arg = "'%s'" % arg
         connection.execution_options(_oursql_plain_query=True).execute(query % arg)
 
diff --git a/lib/sqlalchemy/dialects/mysql/zxjdbc.py b/lib/sqlalchemy/dialects/mysql/zxjdbc.py
index ea01da21c..20f2e7359 100644
--- a/lib/sqlalchemy/dialects/mysql/zxjdbc.py
+++ b/lib/sqlalchemy/dialects/mysql/zxjdbc.py
@@ -37,7 +37,7 @@ class _ZxJDBCBit(BIT):
                 return value
             if isinstance(value, bool):
                 return int(value)
-            v = 0L
+            v = 0
             for i in value:
                 v = v << 8 | (i & 0xff)
             value = v
diff --git a/lib/sqlalchemy/dialects/oracle/base.py b/lib/sqlalchemy/dialects/oracle/base.py
index 831ba5f1b..6b6c32ae0 100644
--- a/lib/sqlalchemy/dialects/oracle/base.py
+++ b/lib/sqlalchemy/dialects/oracle/base.py
@@ -654,14 +654,14 @@ class OracleDDLCompiler(compiler.DDLCompiler):
 class OracleIdentifierPreparer(compiler.IdentifierPreparer):
 
     reserved_words = set([x.lower() for x in RESERVED_WORDS])
-    illegal_initial_characters = set(xrange(0, 10)).union(["_", "$"])
+    illegal_initial_characters = set(range(0, 10)).union(["_", "$"])
 
     def _bindparam_requires_quotes(self, value):
         """Return True if the given identifier requires quoting."""
         lc_value = value.lower()
         return (lc_value in self.reserved_words
                 or value[0] in self.illegal_initial_characters
-                or not self.legal_characters.match(unicode(value))
+                or not self.legal_characters.match(util.text_type(value))
                 )
 
     def format_savepoint(self, savepoint):
@@ -765,10 +765,9 @@ class OracleDialect(default.DefaultDialect):
     def normalize_name(self, name):
         if name is None:
             return None
-        # Py2K
-        if isinstance(name, str):
-            name = name.decode(self.encoding)
-        # end Py2K
+        if util.py2k:
+            if isinstance(name, str):
+                name = name.decode(self.encoding)
         if name.upper() == name and \
               not self.identifier_preparer._requires_quotes(name.lower()):
             return name.lower()
@@ -780,16 +779,15 @@ class OracleDialect(default.DefaultDialect):
             return None
         elif name.lower() == name and not self.identifier_preparer._requires_quotes(name.lower()):
             name = name.upper()
-        # Py2K
-        if not self.supports_unicode_binds:
-            name = name.encode(self.encoding)
-        else:
-            name = unicode(name)
-        # end Py2K
+        if util.py2k:
+            if not self.supports_unicode_binds:
+                name = name.encode(self.encoding)
+            else:
+                name = unicode(name)
         return name
 
     def _get_default_schema_name(self, connection):
-        return self.normalize_name(connection.execute(u'SELECT USER FROM DUAL').scalar())
+        return self.normalize_name(connection.execute('SELECT USER FROM DUAL').scalar())
 
     def _resolve_synonym(self, connection, desired_owner=None, desired_synonym=None, desired_table=None):
         """search for a local synonym matching the given desired owner/name.
@@ -1167,7 +1165,7 @@ class OracleDialect(default.DefaultDialect):
                 local_cols.append(local_column)
                 remote_cols.append(remote_column)
 
-        return fkeys.values()
+        return list(fkeys.values())
 
     @reflection.cache
     def get_view_definition(self, connection, view_name, schema=None,
@@ -1187,7 +1185,9 @@ class OracleDialect(default.DefaultDialect):
 
         rp = connection.execute(sql.text(text), **params).scalar()
         if rp:
-            return rp.decode(self.encoding)
+            if util.py2k:
+                rp = rp.decode(self.encoding)
+            return rp
         else:
             return None
 
diff --git a/lib/sqlalchemy/dialects/oracle/cx_oracle.py b/lib/sqlalchemy/dialects/oracle/cx_oracle.py
index b8f7439f5..e013799db 100644
--- a/lib/sqlalchemy/dialects/oracle/cx_oracle.py
+++ b/lib/sqlalchemy/dialects/oracle/cx_oracle.py
@@ -268,20 +268,17 @@ class _LOBMixin(object):
 
 
 class _NativeUnicodeMixin(object):
-    # Py3K
-    #pass
-    # Py2K
-    def bind_processor(self, dialect):
-        if dialect._cx_oracle_with_unicode:
-            def process(value):
-                if value is None:
-                    return value
-                else:
-                    return unicode(value)
-            return process
-        else:
-            return super(_NativeUnicodeMixin, self).bind_processor(dialect)
-    # end Py2K
+    if util.py2k:
+        def bind_processor(self, dialect):
+            if dialect._cx_oracle_with_unicode:
+                def process(value):
+                    if value is None:
+                        return value
+                    else:
+                        return unicode(value)
+                return process
+            else:
+                return super(_NativeUnicodeMixin, self).bind_processor(dialect)
 
     # we apply a connection output handler that returns
     # unicode in all cases, so the "native_unicode" flag
@@ -493,11 +490,11 @@ class OracleExecutionContext_cx_oracle_with_unicode(OracleExecutionContext_cx_or
     """
     def __init__(self, *arg, **kw):
         OracleExecutionContext_cx_oracle.__init__(self, *arg, **kw)
-        self.statement = unicode(self.statement)
+        self.statement = util.text_type(self.statement)
 
     def _execute_scalar(self, stmt):
         return super(OracleExecutionContext_cx_oracle_with_unicode, self).\
-                            _execute_scalar(unicode(stmt))
+                            _execute_scalar(util.text_type(stmt))
 
 
 class ReturningResultProxy(_result.FullyBufferedResultProxy):
@@ -607,19 +604,23 @@ class OracleDialect_cx_oracle(OracleDialect):
             self.supports_unicode_statements = True
             self.supports_unicode_binds = True
             self._cx_oracle_with_unicode = True
-            # Py2K
-            # There's really no reason to run with WITH_UNICODE under Python 2.x.
-            # Give the user a hint.
-            util.warn("cx_Oracle is compiled under Python 2.xx using the "
-                        "WITH_UNICODE flag.  Consider recompiling cx_Oracle without "
-                        "this flag, which is in no way necessary for full support of Unicode. "
-                        "Otherwise, all string-holding bind parameters must "
-                        "be explicitly typed using SQLAlchemy's String type or one of its subtypes,"
-                        "or otherwise be passed as Python unicode.  Plain Python strings "
-                        "passed as bind parameters will be silently corrupted by cx_Oracle."
-                        )
-            self.execution_ctx_cls = OracleExecutionContext_cx_oracle_with_unicode
-            # end Py2K
+
+            if util.py2k:
+                # There's really no reason to run with WITH_UNICODE under Python 2.x.
+                # Give the user a hint.
+                util.warn(
+                    "cx_Oracle is compiled under Python 2.xx using the "
+                    "WITH_UNICODE flag.  Consider recompiling cx_Oracle "
+                    "without this flag, which is in no way necessary for full "
+                    "support of Unicode. Otherwise, all string-holding bind "
+                    "parameters must be explicitly typed using SQLAlchemy's "
+                    "String type or one of its subtypes,"
+                    "or otherwise be passed as Python unicode.  "
+                    "Plain Python strings passed as bind parameters will be "
+                    "silently corrupted by cx_Oracle."
+                    )
+                self.execution_ctx_cls = \
+                                OracleExecutionContext_cx_oracle_with_unicode
         else:
             self._cx_oracle_with_unicode = False
 
@@ -731,7 +732,7 @@ class OracleDialect_cx_oracle(OracleDialect):
                             arraysize=cursor.arraysize)
             # allow all strings to come back natively as Unicode
             elif defaultType in (cx_Oracle.STRING, cx_Oracle.FIXED_CHAR):
-                return cursor.var(unicode, size, cursor.arraysize)
+                return cursor.var(util.text_type, size, cursor.arraysize)
 
         def on_connect(conn):
             conn.outputtypehandler = output_type_handler
@@ -766,20 +767,19 @@ class OracleDialect_cx_oracle(OracleDialect):
             twophase=self.allow_twophase,
             )
 
-        # Py2K
-        if self._cx_oracle_with_unicode:
-            for k, v in opts.items():
-                if isinstance(v, str):
-                    opts[k] = unicode(v)
-        else:
-            for k, v in opts.items():
-                if isinstance(v, unicode):
-                    opts[k] = str(v)
-        # end Py2K
+        if util.py2k:
+            if self._cx_oracle_with_unicode:
+                for k, v in opts.items():
+                    if isinstance(v, str):
+                        opts[k] = unicode(v)
+            else:
+                for k, v in opts.items():
+                    if isinstance(v, unicode):
+                        opts[k] = str(v)
 
         if 'mode' in url.query:
             opts['mode'] = url.query['mode']
-            if isinstance(opts['mode'], basestring):
+            if isinstance(opts['mode'], util.string_types):
                 mode = opts['mode'].upper()
                 if mode == 'SYSDBA':
                     opts['mode'] = self.dbapi.SYSDBA
@@ -819,6 +819,11 @@ class OracleDialect_cx_oracle(OracleDialect):
         id = random.randint(0, 2 ** 128)
         return (0x1234, "%032x" % id, "%032x" % 9)
 
+    def do_executemany(self, cursor, statement, parameters, context=None):
+        if isinstance(parameters, tuple):
+            parameters = list(parameters)
+        cursor.executemany(statement, parameters)
+
     def do_begin_twophase(self, connection, xid):
         connection.connection.begin(*xid)
 
diff --git a/lib/sqlalchemy/dialects/oracle/zxjdbc.py b/lib/sqlalchemy/dialects/oracle/zxjdbc.py
index d74f21aca..ad53b89a1 100644
--- a/lib/sqlalchemy/dialects/oracle/zxjdbc.py
+++ b/lib/sqlalchemy/dialects/oracle/zxjdbc.py
@@ -95,8 +95,8 @@ class OracleExecutionContext_zxjdbc(OracleExecutionContext):
             try:
                 try:
                     rrs = self.statement.__statement__.getReturnResultSet()
-                    rrs.next()
-                except SQLException, sqle:
+                    next(rrs)
+                except SQLException as sqle:
                     msg = '%s [SQLCode: %d]' % (sqle.getMessage(), sqle.getErrorCode())
                     if sqle.getSQLState() is not None:
                         msg += ' [SQLState: %s]' % sqle.getSQLState()
diff --git a/lib/sqlalchemy/dialects/postgresql/base.py b/lib/sqlalchemy/dialects/postgresql/base.py
index 1acdb57b9..00d0acc2c 100644
--- a/lib/sqlalchemy/dialects/postgresql/base.py
+++ b/lib/sqlalchemy/dialects/postgresql/base.py
@@ -188,7 +188,6 @@ underlying CREATE INDEX command, so it *must* be a valid index type for your
 version of PostgreSQL.
 
 """
-
 import re
 
 from ... import sql, schema, exc, util
@@ -333,7 +332,7 @@ class UUID(sqltypes.TypeEngine):
         if self.as_uuid:
             def process(value):
                 if value is not None:
-                    value = str(value)
+                    value = util.text_type(value)
                 return value
             return process
         else:
@@ -1419,7 +1418,7 @@ class PGDialect(default.DefaultDialect):
                 query,
                 bindparams=[
                     sql.bindparam(
-                        'schema', unicode(schema.lower()),
+                        'schema', util.text_type(schema.lower()),
                         type_=sqltypes.Unicode)]
             )
         )
@@ -1435,7 +1434,7 @@ class PGDialect(default.DefaultDialect):
                 "n.oid=c.relnamespace where n.nspname=current_schema() and "
                 "relname=:name",
                 bindparams=[
-                        sql.bindparam('name', unicode(table_name),
+                        sql.bindparam('name', util.text_type(table_name),
                         type_=sqltypes.Unicode)]
                 )
             )
@@ -1447,9 +1446,9 @@ class PGDialect(default.DefaultDialect):
                 "relname=:name",
                     bindparams=[
                         sql.bindparam('name',
-                        unicode(table_name), type_=sqltypes.Unicode),
+                        util.text_type(table_name), type_=sqltypes.Unicode),
                         sql.bindparam('schema',
-                        unicode(schema), type_=sqltypes.Unicode)]
+                        util.text_type(schema), type_=sqltypes.Unicode)]
                 )
             )
         return bool(cursor.first())
@@ -1463,7 +1462,7 @@ class PGDialect(default.DefaultDialect):
                     "n.nspname=current_schema() "
                     "and relname=:name",
                     bindparams=[
-                        sql.bindparam('name', unicode(sequence_name),
+                        sql.bindparam('name', util.text_type(sequence_name),
                         type_=sqltypes.Unicode)
                     ]
                 )
@@ -1475,10 +1474,10 @@ class PGDialect(default.DefaultDialect):
                 "n.oid=c.relnamespace where relkind='S' and "
                 "n.nspname=:schema and relname=:name",
                 bindparams=[
-                    sql.bindparam('name', unicode(sequence_name),
+                    sql.bindparam('name', util.text_type(sequence_name),
                      type_=sqltypes.Unicode),
                     sql.bindparam('schema',
-                                unicode(schema), type_=sqltypes.Unicode)
+                                util.text_type(schema), type_=sqltypes.Unicode)
                 ]
             )
             )
@@ -1488,9 +1487,9 @@ class PGDialect(default.DefaultDialect):
     def has_type(self, connection, type_name, schema=None):
         bindparams = [
             sql.bindparam('typname',
-                unicode(type_name), type_=sqltypes.Unicode),
+                util.text_type(type_name), type_=sqltypes.Unicode),
             sql.bindparam('nspname',
-                unicode(schema), type_=sqltypes.Unicode),
+                util.text_type(schema), type_=sqltypes.Unicode),
             ]
         if schema is not None:
             query = """
@@ -1546,9 +1545,9 @@ class PGDialect(default.DefaultDialect):
         """ % schema_where_clause
         # Since we're binding to unicode, table_name and schema_name must be
         # unicode.
-        table_name = unicode(table_name)
+        table_name = util.text_type(table_name)
         if schema is not None:
-            schema = unicode(schema)
+            schema = util.text_type(schema)
         s = sql.text(query, bindparams=[
             sql.bindparam('table_name', type_=sqltypes.Unicode),
             sql.bindparam('schema', type_=sqltypes.Unicode)
@@ -1570,13 +1569,13 @@ class PGDialect(default.DefaultDialect):
         """
         rp = connection.execute(s)
         # what about system tables?
-        # Py3K
-        #schema_names = [row[0] for row in rp \
-        #                if not row[0].startswith('pg_')]
-        # Py2K
-        schema_names = [row[0].decode(self.encoding) for row in rp \
+
+        if util.py2k:
+            schema_names = [row[0].decode(self.encoding) for row in rp \
+                        if not row[0].startswith('pg_')]
+        else:
+            schema_names = [row[0] for row in rp \
                         if not row[0].startswith('pg_')]
-        # end Py2K
         return schema_names
 
     @reflection.cache
@@ -1587,7 +1586,7 @@ class PGDialect(default.DefaultDialect):
             current_schema = self.default_schema_name
 
         result = connection.execute(
-            sql.text(u"SELECT relname FROM pg_class c "
+            sql.text("SELECT relname FROM pg_class c "
                 "WHERE relkind = 'r' "
                 "AND '%s' = (select nspname from pg_namespace n "
                 "where n.oid = c.relnamespace) " %
@@ -1610,12 +1609,12 @@ class PGDialect(default.DefaultDialect):
           AND '%(schema)s' = (select nspname from pg_namespace n
           where n.oid = c.relnamespace)
         """ % dict(schema=current_schema)
-        # Py3K
-        #view_names = [row[0] for row in connection.execute(s)]
-        # Py2K
-        view_names = [row[0].decode(self.encoding)
+
+        if util.py2k:
+            view_names = [row[0].decode(self.encoding)
                             for row in connection.execute(s)]
-        # end Py2K
+        else:
+            view_names = [row[0] for row in connection.execute(s)]
         return view_names
 
     @reflection.cache
@@ -1632,11 +1631,10 @@ class PGDialect(default.DefaultDialect):
         rp = connection.execute(sql.text(s),
                                 view_name=view_name, schema=current_schema)
         if rp:
-            # Py3K
-            #view_def = rp.scalar()
-            # Py2K
-            view_def = rp.scalar().decode(self.encoding)
-            # end Py2K
+            if util.py2k:
+                view_def = rp.scalar().decode(self.encoding)
+            else:
+                view_def = rp.scalar()
             return view_def
 
     @reflection.cache
diff --git a/lib/sqlalchemy/dialects/postgresql/hstore.py b/lib/sqlalchemy/dialects/postgresql/hstore.py
index 4daf54bab..d7368ff42 100644
--- a/lib/sqlalchemy/dialects/postgresql/hstore.py
+++ b/lib/sqlalchemy/dialects/postgresql/hstore.py
@@ -97,14 +97,14 @@ def _serialize_hstore(val):
     def esc(s, position):
         if position == 'value' and s is None:
             return 'NULL'
-        elif isinstance(s, basestring):
+        elif isinstance(s, util.string_types):
             return '"%s"' % s.replace('"', r'\"')
         else:
             raise ValueError("%r in %s position is not a string." %
                              (s, position))
 
     return ', '.join('%s=>%s' % (esc(k, 'key'), esc(v, 'value'))
-                     for k, v in val.iteritems())
+                     for k, v in val.items())
 
 
 class HSTORE(sqltypes.Concatenable, sqltypes.TypeEngine):
diff --git a/lib/sqlalchemy/dialects/postgresql/psycopg2.py b/lib/sqlalchemy/dialects/postgresql/psycopg2.py
index c796c99c7..fcc1946ff 100644
--- a/lib/sqlalchemy/dialects/postgresql/psycopg2.py
+++ b/lib/sqlalchemy/dialects/postgresql/psycopg2.py
@@ -143,6 +143,7 @@ effect for other DBAPIs.
 
 """
 from __future__ import absolute_import
+
 import re
 import logging
 
@@ -190,22 +191,20 @@ class _PGNumeric(sqltypes.Numeric):
 class _PGEnum(ENUM):
     def __init__(self, *arg, **kw):
         super(_PGEnum, self).__init__(*arg, **kw)
-        # Py2K
-        if self.convert_unicode:
-            self.convert_unicode = "force"
-        # end Py2K
+        if util.py2k:
+            if self.convert_unicode:
+                self.convert_unicode = "force"
 
 
 class _PGArray(ARRAY):
     def __init__(self, *arg, **kw):
         super(_PGArray, self).__init__(*arg, **kw)
-        # Py2K
-        # FIXME: this check won't work for setups that
-        # have convert_unicode only on their create_engine().
-        if isinstance(self.item_type, sqltypes.String) and \
-                    self.item_type.convert_unicode:
-            self.item_type.convert_unicode = "force"
-        # end Py2K
+        if util.py2k:
+            # FIXME: this check won't work for setups that
+            # have convert_unicode only on their create_engine().
+            if isinstance(self.item_type, sqltypes.String) and \
+                        self.item_type.convert_unicode:
+                self.item_type.convert_unicode = "force"
 
 
 class _PGHStore(HSTORE):
@@ -294,9 +293,9 @@ class PGIdentifierPreparer_psycopg2(PGIdentifierPreparer):
 
 class PGDialect_psycopg2(PGDialect):
     driver = 'psycopg2'
-    # Py2K
-    supports_unicode_statements = False
-    # end Py2K
+    if util.py2k:
+        supports_unicode_statements = False
+
     default_paramstyle = 'pyformat'
     supports_sane_multi_rowcount = False
     execution_ctx_cls = PGExecutionContext_psycopg2
diff --git a/lib/sqlalchemy/dialects/sqlite/base.py b/lib/sqlalchemy/dialects/sqlite/base.py
index f21a81d0c..1ca8f4e64 100644
--- a/lib/sqlalchemy/dialects/sqlite/base.py
+++ b/lib/sqlalchemy/dialects/sqlite/base.py
@@ -508,7 +508,7 @@ class SQLiteDDLCompiler(compiler.DDLCompiler):
 
     def visit_foreign_key_constraint(self, constraint):
 
-        local_table = constraint._elements.values()[0].parent.table
+        local_table = list(constraint._elements.values())[0].parent.table
         remote_table = list(constraint._elements.values())[0].column.table
 
         if local_table.schema != remote_table.schema:
@@ -812,7 +812,7 @@ class SQLiteDialect(default.DefaultDialect):
             coltype = sqltypes.NullType()
 
         if default is not None:
-            default = unicode(default)
+            default = util.text_type(default)
 
         return {
             'name': name,
diff --git a/lib/sqlalchemy/dialects/sqlite/pysqlite.py b/lib/sqlalchemy/dialects/sqlite/pysqlite.py
index d827607ba..ad0dd5292 100644
--- a/lib/sqlalchemy/dialects/sqlite/pysqlite.py
+++ b/lib/sqlalchemy/dialects/sqlite/pysqlite.py
@@ -267,8 +267,8 @@ class SQLiteDialect_pysqlite(SQLiteDialect):
         }
     )
 
-    # Py3K
-    #description_encoding = None
+    if not util.py2k:
+        description_encoding = None
 
     driver = 'pysqlite'
 
@@ -288,7 +288,7 @@ class SQLiteDialect_pysqlite(SQLiteDialect):
     def dbapi(cls):
         try:
             from pysqlite2 import dbapi2 as sqlite
-        except ImportError, e:
+        except ImportError as e:
             try:
                 from sqlite3 import dbapi2 as sqlite  # try 2.5+ stdlib name.
             except ImportError:
diff --git a/lib/sqlalchemy/dialects/sybase/__init__.py b/lib/sqlalchemy/dialects/sybase/__init__.py
index 7d504e54e..f61352ceb 100644
--- a/lib/sqlalchemy/dialects/sybase/__init__.py
+++ b/lib/sqlalchemy/dialects/sybase/__init__.py
@@ -9,7 +9,7 @@ from sqlalchemy.dialects.sybase import base, pysybase, pyodbc
 # default dialect
 base.dialect = pyodbc.dialect
 
-from base import CHAR, VARCHAR, TIME, NCHAR, NVARCHAR,\
+from .base import CHAR, VARCHAR, TIME, NCHAR, NVARCHAR,\
                  TEXT, DATE, DATETIME, FLOAT, NUMERIC,\
                  BIGINT, INT, INTEGER, SMALLINT, BINARY,\
                  VARBINARY, UNITEXT, UNICHAR, UNIVARCHAR,\
diff --git a/lib/sqlalchemy/dialects/sybase/base.py b/lib/sqlalchemy/dialects/sybase/base.py
index a9e5c5fda..6770ed8e7 100644
--- a/lib/sqlalchemy/dialects/sybase/base.py
+++ b/lib/sqlalchemy/dialects/sybase/base.py
@@ -475,12 +475,12 @@ class SybaseDialect(default.DefaultDialect):
               AND o.type in ('U', 'V')
         """)
 
-        # Py2K
-        if isinstance(schema, unicode):
-            schema = schema.encode("ascii")
-        if isinstance(table_name, unicode):
-            table_name = table_name.encode("ascii")
-        # end Py2K
+# start Py2K
+#        if isinstance(schema, unicode):
+#            schema = schema.encode("ascii")
+#        if isinstance(table_name, unicode):
+#            table_name = table_name.encode("ascii")
+# end Py2K
         result = connection.execute(TABLEID_SQL,
                                     schema_name=schema,
                                     table_name=table_name)
@@ -759,10 +759,10 @@ class SybaseDialect(default.DefaultDialect):
             AND o.type = 'U'
         """)
 
-        # Py2K
-        if isinstance(schema, unicode):
-            schema = schema.encode("ascii")
-        # end Py2K
+# start Py2K
+#        if isinstance(schema, unicode):
+#            schema = schema.encode("ascii")
+# end Py2K
         tables = connection.execute(TABLE_SQL, schema_name=schema)
 
         return [t["name"] for t in tables]
@@ -779,10 +779,10 @@ class SybaseDialect(default.DefaultDialect):
             AND o.type = 'V'
         """)
 
-        # Py2K
-        if isinstance(view_name, unicode):
-            view_name = view_name.encode("ascii")
-        # end Py2K
+# start Py2K
+#        if isinstance(view_name, unicode):
+#            view_name = view_name.encode("ascii")
+# end Py2K
         view = connection.execute(VIEW_DEF_SQL, view_name=view_name)
 
         return view.scalar()
@@ -799,10 +799,10 @@ class SybaseDialect(default.DefaultDialect):
             AND o.type = 'V'
         """)
 
-        # Py2K
-        if isinstance(schema, unicode):
-            schema = schema.encode("ascii")
-        # end Py2K
+# start Py2K
+#        if isinstance(schema, unicode):
+#            schema = schema.encode("ascii")
+# end Py2K
         views = connection.execute(VIEW_SQL, schema_name=schema)
 
         return [v["name"] for v in views]