bpo-33131: Upgrade ensurepip to bundle pip 10.0.1 (GH-6546)

Upgrade ensurepip to bundle pip 10.0.1
(cherry picked from commit 0399cf9)

Co-authored-by: Paul Moore <p.f.moore@gmail.com>

Author: miss-islington

Lib/ensurepip/__init__.py

@@ -14,7 +14,7 @@
 
 _SETUPTOOLS_VERSION = "39.0.1"
 
-_PIP_VERSION = "9.0.3"
+_PIP_VERSION = "10.0.1"
 
 _PROJECTS = [
     ("setuptools", _SETUPTOOLS_VERSION),
@@ -28,8 +28,8 @@ def _run_pip(args, additional_paths=None):
         sys.path = additional_paths + sys.path
 
     # Install the bundled software
-    import pip
-    return pip.main(args)
+    import pip._internal
+    return pip._internal.main(args)
 
 
 def version():

Lib/ensurepip/_bundled/pip-10.0.1-py2.py3-none-any.whl

@@ -0,0 +1 @@
+Upgrade bundled version of pip to 10.0.1.