Merge pull request pypa#10943 from pradyunsg/downgrade-distlib

Downgrade to distlib 0.3.3

news/distlib.vendor.rst

@@ -0,0 +1 @@
+Downgrade distlib to 0.3.3.

src/pip/_vendor/distlib/__init__.py

@@ -6,7 +6,7 @@
 #
 import logging
 
-__version__ = '0.3.4'
+__version__ = '0.3.3'
 
 class DistlibException(Exception):
     pass

src/pip/_vendor/distlib/_backport/__init__.py

@@ -0,0 +1,6 @@
+"""Modules copied from Python 3 standard libraries, for internal use only.
+
+Individual classes and functions are found in d2._backport.misc.  Intended
+usage is to always import things missing from 3.1 from that module: the
+built-in/stdlib objects will be used if found.
+"""

src/pip/_vendor/distlib/_backport/misc.py

@@ -0,0 +1,41 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2012 The Python Software Foundation.
+# See LICENSE.txt and CONTRIBUTORS.txt.
+#
+"""Backports for individual classes and functions."""
+
+import os
+import sys
+
+__all__ = ['cache_from_source', 'callable', 'fsencode']
+
+
+try:
+    from imp import cache_from_source
+except ImportError:
+    def cache_from_source(py_file, debug=__debug__):
+        ext = debug and 'c' or 'o'
+        return py_file + ext
+
+
+try:
+    callable = callable
+except NameError:
+    from collections import Callable
+
+    def callable(obj):
+        return isinstance(obj, Callable)
+
+
+try:
+    fsencode = os.fsencode
+except AttributeError:
+    def fsencode(filename):
+        if isinstance(filename, bytes):
+            return filename
+        elif isinstance(filename, str):
+            return filename.encode(sys.getfilesystemencoding())
+        else:
+            raise TypeError("expect bytes or str, not %s" %
+                            type(filename).__name__)