Pip 19.0.3 -> 19.2.3 fails with AttributeError: 'NoneType' object has no attribute 'bytes'

Environment

• pip version: 19.0.3
• Python version: 3.7.4 (tags/v3.7.4:e09359112e, Jul 8 2019, 20:34:20) [MSC v.1916 64 bit (AMD64)] on win32
• OS: Win10 (1809, 17763.737)

Description Error occurs during upgrade.

Expected behavior pip installs without error.

How to Reproduce

1. Download Python 3.7.4 from https://www.python.org/downloads/release/python-374/ (web-based installer)
2. Install for all users
3. Open cmd / PowerShell as admin
4. C:\WINDOWS\system32>python -m pip install --upgrade pip

Output

Collecting pip
  Using cached https://files.pythonhosted.org/packages/30/db/9e38760b32e3e7f40cce46dd5fb107b8c73840df38f0046d8e6514e675a1/pip-19.2.3-py2.py3-none-any.whl
Installing collected packages: pip
  Found existing installation: pip 19.0.3
    Uninstalling pip-19.0.3:
      Successfully uninstalled pip-19.0.3
  Rolling back uninstall of pip
  Moving to c:\users\user\appdata\roaming\python\python37\scripts\pip.exe
   from C:\Users\User\AppData\Local\Temp\pip-uninstall-akvm93y4\pip.exe
  Moving to c:\users\user\appdata\roaming\python\python37\scripts\pip3.7.exe
   from C:\Users\User\AppData\Local\Temp\pip-uninstall-akvm93y4\pip3.7.exe
  Moving to c:\users\user\appdata\roaming\python\python37\scripts\pip3.exe
   from C:\Users\User\AppData\Local\Temp\pip-uninstall-akvm93y4\pip3.exe
  Moving to c:\users\user\appdata\roaming\python\python37\site-packages\pip-19.0.3.dist-info\
   from c:\users\user\appdata\roaming\python\python37\site-packages\~ip-19.0.3.dist-info
  Moving to c:\users\user\appdata\roaming\python\python37\site-packages\pip\
   from c:\users\user\appdata\roaming\python\python37\site-packages\~ip
Exception:
Traceback (most recent call last):
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\cli\base_command.py", line 179, in main
    status = self.run(options, args)
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\commands\install.py", line 393, in run
    use_user_site=options.use_user_site,
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\req\__init__.py", line 57, in install_given_reqs
    **kwargs
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\req\req_install.py", line 913, in install
    use_user_site=use_user_site, pycompile=pycompile,
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\req\req_install.py", line 445, in move_wheel_files
    warn_script_location=warn_script_location,
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\wheel.py", line 544, in move_wheel_files
    generated.extend(maker.make(spec))
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\distlib\scripts.py", line 405, in make
    self._make_script(entry, filenames, options=options)
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\distlib\scripts.py", line 309, in _make_script
    self._write_script(scriptnames, shebang, script, filenames, ext)
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\distlib\scripts.py", line 245, in _write_script
    launcher = self._get_launcher('t')
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\distlib\scripts.py", line 384, in _get_launcher
    result = finder(distlib_package).find(name).bytes
AttributeError: 'NoneType' object has no attribute 'bytes'
You are using pip version 19.0.3, however version 19.2.3 is available.
You should consider upgrading via the 'python -m pip install --upgrade pip' command.

I also tried using solution from https://github.com/pypa/pip/issues/5820#issuecomment-428611054

C:\WINDOWS\system32>python -m pip install -U --force-reinstall pip
Collecting pip
  Using cached https://files.pythonhosted.org/packages/30/db/9e38760b32e3e7f40cce46dd5fb107b8c73840df38f0046d8e6514e675a1/pip-19.2.3-py2.py3-none-any.whl
Installing collected packages: pip
  Found existing installation: pip 19.0.3
    Uninstalling pip-19.0.3:
      Successfully uninstalled pip-19.0.3
  Rolling back uninstall of pip
  Moving to c:\users\user\appdata\roaming\python\python37\scripts\pip.exe
   from C:\Users\User\AppData\Local\Temp\pip-uninstall-1kl45zbn\pip.exe
  Moving to c:\users\user\appdata\roaming\python\python37\scripts\pip3.7.exe
   from C:\Users\User\AppData\Local\Temp\pip-uninstall-1kl45zbn\pip3.7.exe
  Moving to c:\users\user\appdata\roaming\python\python37\scripts\pip3.exe
   from C:\Users\User\AppData\Local\Temp\pip-uninstall-1kl45zbn\pip3.exe
  Moving to c:\users\user\appdata\roaming\python\python37\site-packages\pip-19.0.3.dist-info\
   from c:\users\user\appdata\roaming\python\python37\site-packages\~ip-19.0.3.dist-info
  Moving to c:\users\user\appdata\roaming\python\python37\site-packages\pip\
   from c:\users\user\appdata\roaming\python\python37\site-packages\~ip
Exception:
Traceback (most recent call last):
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\cli\base_command.py", line 179, in main
    status = self.run(options, args)
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\commands\install.py", line 393, in run
    use_user_site=options.use_user_site,
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\req\__init__.py", line 57, in install_given_reqs
    **kwargs
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\req\req_install.py", line 913, in install
    use_user_site=use_user_site, pycompile=pycompile,
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\req\req_install.py", line 445, in move_wheel_files
    warn_script_location=warn_script_location,
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_internal\wheel.py", line 544, in move_wheel_files
    generated.extend(maker.make(spec))
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\distlib\scripts.py", line 405, in make
    self._make_script(entry, filenames, options=options)
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\distlib\scripts.py", line 309, in _make_script
    self._write_script(scriptnames, shebang, script, filenames, ext)
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\distlib\scripts.py", line 245, in _write_script
    launcher = self._get_launcher('t')
  File "C:\Users\User\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\distlib\scripts.py", line 384, in _get_launcher
    result = finder(distlib_package).find(name).bytes
AttributeError: 'NoneType' object has no attribute 'bytes'
You are using pip version 19.0.3, however version 19.2.3 is available.
You should consider upgrading via the 'python -m pip install --upgrade pip' command.

[tonystevenj]

“easy_install -U pip” works!

[mrsmirzaee]

I uesd ithis command " easy_install -U pip " and work for me