Update Black's target-version to py37

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### Description
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Black's `target-version` was still set to `['py27', 'py36']`. Set it to `[py37]` instead.

Also update Black and other pre-commit hooks and re-format with Black.

### Checklist
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This pull request is:

- [ ] A documentation / typographical error fix
	- Good to go, no issue or tests are needed
- [ ] A short code fix
	- please include the issue number, and create an issue if none exists, which
	  must include a complete example of the issue.  one line code fixes without an
	  issue and demonstration will not be accepted.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.   one line code fixes without tests will not be accepted.
- [ ] A new feature implementation
	- please include the issue number, and create an issue if none exists, which must
	  include a complete example of how the feature would look.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.

**Have a nice day!**

Closes: #7536
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/7536
Pull-request-sha: b3aedf5570d7e0ba6c354e5989835260d0591b08

Change-Id: I8be85636fd2c9449b07a8626050c8bd35bd119d5

3 files changed, 7 insertions, 4 deletions

diff --git a/test/engine/test_parseconnect.py b/test/engine/test_parseconnect.py
index 19fce5c18..00d9390b4 100644
--- a/test/engine/test_parseconnect.py
+++ b/test/engine/test_parseconnect.py
@@ -319,7 +319,7 @@ class URLTest(fixtures.TestBase):
             "%s must be a string" % argname,
             url.URL.create,
             "somedriver",
-            **{argname: value}
+            **{argname: value},
         )
 
     @testing.combinations("username", "host", "database", argnames="argname")
@@ -352,7 +352,7 @@ class URLTest(fixtures.TestBase):
             TypeError,
             "%s must be a string" % argname,
             u1.set,
-            **{argname: 35.8}
+            **{argname: 35.8},
         )
 
     def test_only_str_query_key_constructor(self):
diff --git a/test/engine/test_reconnect.py b/test/engine/test_reconnect.py
index f37d1893f..74b5b2df5 100644
--- a/test/engine/test_reconnect.py
+++ b/test/engine/test_reconnect.py
@@ -173,7 +173,7 @@ class PrePingMockTest(fixtures.TestBase):
             creator=lambda: self.dbapi.connect("foo.db"),
             pre_ping=pre_ping,
             dialect=dialect,
-            **(pool_kw if pool_kw else {})
+            **(pool_kw if pool_kw else {}),
         )
 
         dialect.is_disconnect = lambda e, conn, cursor: isinstance(
diff --git a/test/engine/test_reflection.py b/test/engine/test_reflection.py
index efd30071e..42c83d87b 100644
--- a/test/engine/test_reflection.py
+++ b/test/engine/test_reflection.py
@@ -257,7 +257,10 @@ class ReflectionTest(fixtures.TestBase, ComparesTables):
         foo = Table(
             "foo",
             meta,
-            *[Column(n, sa.String(30)) for n in ["a", "b", "c", "d", "e", "f"]]
+            *[
+                Column(n, sa.String(30))
+                for n in ["a", "b", "c", "d", "e", "f"]
+            ],
         )
         meta.create_all(connection)
         meta2 = MetaData()