Copy updated urllib from CPython 3.8.3.

Author: skinnyBat

Lib/urllib/error.py

@@ -16,14 +16,10 @@
 __all__ = ['URLError', 'HTTPError', 'ContentTooShortError']
 
 
-# do these error classes make sense?
-# make sure all of the OSError stuff is overridden.  we just want to be
-# subtypes.
-
 class URLError(OSError):
     # URLError is a sub-type of OSError, but it doesn't share any of
     # the implementation.  need to override __init__ and __str__.
-    # It sets self.args for compatibility with other EnvironmentError
+    # It sets self.args for compatibility with other OSError
     # subclasses, but args doesn't have the typical format with errno in
     # slot 0 and strerror in slot 1.  This may be better than nothing.
     def __init__(self, reason, filename=None):