tweaks to hierarchy to improve load times

I think that most of the difference actually comes from patching uuid
to not waste 25 milliseconds every time it is imported but there is a
bit of improvement here

3 files changed, 7 insertions, 10 deletions

diff --git a/rdflib/container.py b/rdflib/container.py
index ca884a4e..b5679e3e 100644
--- a/rdflib/container.py
+++ b/rdflib/container.py
@@ -1,6 +1,5 @@
 from rdflib.namespace import RDF
-from rdflib.term import BNode
-from rdflib import URIRef
+from rdflib.term import BNode, URIRef
 from random import randint
 
 __all__ = ["Container", "Bag", "Seq", "Alt", "NoElementException"]
diff --git a/rdflib/namespace.py b/rdflib/namespace.py
index bdb0000a..61fd5d85 100644
--- a/rdflib/namespace.py
+++ b/rdflib/namespace.py
@@ -1,10 +1,8 @@
 import logging
 
-import os
 from unicodedata import category
 
-
-from urllib.request import pathname2url
+from pathlib import Path
 from urllib.parse import urldefrag
 from urllib.parse import urljoin
 
@@ -850,7 +848,7 @@ class NamespaceManager(object):
             yield prefix, namespace
 
     def absolutize(self, uri, defrag=1):
-        base = urljoin("file:", pathname2url(os.getcwd()))
+        base = Path.cwd().as_uri()
         result = urljoin("%s/" % base, uri, allow_fragments=not defrag)
         if defrag:
             result = urldefrag(result)[0]
diff --git a/rdflib/parser.py b/rdflib/parser.py
index a6f155a6..7dd9185d 100644
--- a/rdflib/parser.py
+++ b/rdflib/parser.py
@@ -17,7 +17,6 @@ import sys
 
 from io import BytesIO, TextIOBase, TextIOWrapper, StringIO, BufferedIOBase
 
-from urllib.request import pathname2url
 from urllib.request import Request
 from urllib.request import url2pathname
 from urllib.parse import urljoin
@@ -285,10 +284,11 @@ def create_input_source(
 
 def _create_input_source_from_location(file, format, input_source, location):
     # Fix for Windows problem https://github.com/RDFLib/rdflib/issues/145
-    if os.path.exists(location):
-        location = pathname2url(location)
+    location = pathlib.Path(location)
+    if location.exists():
+        location = location.as_uri()
 
-    base = urljoin("file:", "%s/" % pathname2url(os.getcwd()))
+    base = pathlib.Path.cwd().as_uri()
 
     absolute_location = URIRef(location, base=base)