下的3.5版本,pip install pyinstaller 安装报错

C:\Users\mn>pip install pyinstaller
DEPRECATION: Python 3.5 reached the end of its life on September 13th, 2020. Please upgrade your Python as Python 3.5 is no longer maintained. pip 21.0 will drop support for Python 3.5 in January 2021. pip 21.0 will remove support for this functionality.
Collecting pyinstaller
  Downloading pyinstaller-4.2.tar.gz (3.6 MB)
     |████████████████████████████████| 3.6 MB 23 kB/s
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
ERROR: Exception:
Traceback (most recent call last):
  File "d:\python\py\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 171, in _merge_into_criterion
    crit = self.state.criteria[name]
KeyError: 'pyinstaller'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
  File "d:\python\py\lib\site-packages\pip\_internal\cli\base_command.py", line 223, in _main
    status = self.run(options, args)
  File "d:\python\py\lib\site-packages\pip\_internal\cli\req_command.py", line 180, in wrapper
    return func(self, options, args)
  File "d:\python\py\lib\site-packages\pip\_internal\commands\install.py", line 321, in run
    reqs, check_supported_wheels=not options.target_dir
  File "d:\python\py\lib\site-packages\pip\_internal\resolution\resolvelib\resolver.py", line 122, in resolve
    requirements, max_rounds=try_to_avoid_resolution_too_deep,
  File "d:\python\py\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 453, in resolve
    state = resolution.resolve(requirements, max_rounds=max_rounds)
  File "d:\python\py\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 318, in resolve
    name, crit = self._merge_into_criterion(r, parent=None)
  File "d:\python\py\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 173, in _merge_into_criterion
    crit = Criterion.from_requirement(self._p, requirement, parent)
  File "d:\python\py\lib\site-packages\pip\_vendor\resolvelib\resolvers.py", line 82, in from_requirement
    if not cands:
  File "d:\python\py\lib\site-packages\pip\_vendor\resolvelib\structs.py", line 124, in __bool__
    return bool(self._sequence)
  File "d:\python\py\lib\site-packages\pip\_internal\resolution\resolvelib\found_candidates.py", line 99, in __bool__
    return any(self)
  File "d:\python\py\lib\site-packages\pip\_internal\resolution\resolvelib\factory.py", line 244, in iter_index_candidates
    version=ican.version,

解决方法:

更换下载源:
豆瓣源 : http://pypi.douban.com/simple/
清华源: https://pypi.tuna.tsinghua.edu.cn/simple
使用方法 : pip install -i https://pypi.tuna.tsinghua.edu.cn/simple pyinstaller
pyinstaller使用 : https://www.cnblogs.com/songhaixing/p/14128815.html