(Issue #17807: Generators can now be finalized even when they are part of a reference cycle)

  in urllib.request.urlopen() is fixed to match the code.

  in urllib.request.urlopen() is fixed to match the code.

characters() and ignorableWhitespace() methods.  Original patch by Sebastian
Ortiz Vasquez.

characters() and ignorableWhitespace() methods.  Original patch by Sebastian
Ortiz Vasquez.

distutils.cfg when a venv is active.

codecs.open().

broke backwards compatibility.