pip 在 Mac Mojave 上无法运行

Question

当我尝试在 Mac Mojave 上使用 pip 命令时，收到此错误：

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/pkg_resources/__init__.py", line 583, in _build_master
    ws.require(__requires__)
  File "/usr/local/lib/python3.7/site-packages/pkg_resources/__init__.py", line 900, in require
    needed = self.resolve(parse_requirements(requirements))
  File "/usr/local/lib/python3.7/site-packages/pkg_resources/__init__.py", line 791, in resolve
    raise VersionConflict(dist, req).with_context(dependent_req)
pkg_resources.VersionConflict: (pip 19.2.1 (/usr/local/lib/python3.7/site-packages), Requirement.parse('pip==19.1.1'))

在处理上述异常的过程中，又发生了另一个异常：

Traceback (most recent call last):
  File "/usr/local/opt/python/libexec/bin/pip", line 6, in <module>
    from pkg_resources import load_entry_point
  File "/usr/local/lib/python3.7/site-packages/pkg_resources/__init__.py", line 3241, in <module>
    @_call_aside
  File "/usr/local/lib/python3.7/site-packages/pkg_resources/__init__.py", line 3225, in _call_aside
    f(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/pkg_resources/__init__.py", line 3254, in _initialize_master_working_set
    working_set = WorkingSet._build_master()
  File "/usr/local/lib/python3.7/site-packages/pkg_resources/__init__.py", line 585, in _build_master
    return cls._build_from_requirements(__requires__)
  File "/usr/local/lib/python3.7/site-packages/pkg_resources/__init__.py", line 598, in _build_from_requirements
    dists = ws.resolve(reqs, Environment())
  File "/usr/local/lib/python3.7/site-packages/pkg_resources/__init__.py", line 786, in resolve
    raise DistributionNotFound(req, requirers)
pkg_resources.DistributionNotFound: The 'pip==19.1.1' distribution was not found and is required by the application

我该如何修复它？

Answer 1

由于缺乏有关 Python 项目、pip 版本和实际命令的详细信息，我只能推断出现此错误消息是因为您的 Python 项目明确请求了pip 19.1.2。例如，您的 requirements.txt 文件可能有

pip=19.1.2

使用更宽松的版本依赖性

您可以将要求更改为

pip>=19.1.0,<=20.0

升级 pip

升级pip到最新版本

pip install --upgrade pip