ImportError:无法从'pip._internal.distributions.source‘导入名称'SourceDistribution’

Question

pip3 install不工作，而且pip3也不能从Pip20.0降级到pip19：

Rayaans-MacBook-Pro:~ rayaangrewal$ pip3 install 
    Traceback (most recent call last):
      File "/Library/Frameworks/Python.framework/Versions/3.7/bin/pip3", line 10, in <module>
        sys.exit(main())
      File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pip/_internal/cli/main.py", line 73, in main
        command = create_command(cmd_name, isolated=("--isolated" in cmd_args))
      File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pip/_internal/commands/__init__.py", line 96, in create_command
        module = importlib.import_module(module_path)
      File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/importlib/__init__.py", line 127, in import_module
        return _bootstrap._gcd_import(name[level:], package, level)
      File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
      File "<frozen importlib._bootstrap>", line 983, in _find_and_load
      File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
      File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
      File "<frozen importlib._bootstrap_external>", line 728, in exec_module
      File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
      File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pip/_internal/commands/install.py", line 24, in <module>
        from pip._internal.cli.req_command import RequirementCommand
      File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pip/_internal/cli/req_command.py", line 20, in <module>
        from pip._internal.operations.prepare import RequirementPreparer
      File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pip/_internal/operations/prepare.py", line 16, in <module>
        from pip._internal.distributions import (
      File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pip/_internal/distributions/__init__.py", line 1, in <module>
        from pip._internal.distributions.source import SourceDistribution
    ImportError: cannot import name 'SourceDistribution' from 'pip._internal.distributions.source' (/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pip/_internal/distributions/source/__init__.py)

Answer 1

这是pip 20.0中的一个错误；请参阅https://github.com/pypa/pip/issues/7620

它已在pip 20.0.1中修复。升级到20.0.1+或降级到19.3.1。获取get-pip.py并运行

python get-pip.py

或

python get-pip.py pip==19.3.1

Answer 2

在@pdh的github问题链接中回答得很好。

当在Ubuntu/LXC上使用 3.6+中的Python venv时，在执行过程中使用自安装/自升级pip命令时，可以使用get-pip.py：

bin/pip3 install --upgrade pip

• You可以使用：

1. 激活虚拟环境venv：
2. 而不是自更新pip命令(在pip 0.20.0中不起作用)

cd bin
# downloading get-pip.py each time; but you could also remove it from here
# and run this manually only once:
wget https://bootstrap.pypa.io/get-pip.py -O ./get-pip.py
# definitely keep this command:
python3 get-pip.py
cd ..

结果：

Collecting pip
...
Installing collected packages: pip
  Found existing installation: pip 20.0.0
    Uninstalling pip-20.0.0:
      Successfully uninstalled pip-20.0.0
Successfully installed pip-20.0.1

get-pip.py备注：

除非--force-reinstall

• It或--no-wheel

特别禁用，否则

• 它将升级该/bin文件夹中的所有现有pip应用程序(例如pip、pip3、

3.6)，并且它将固有地使用参数install、--upgrade、--force-reinstall

• It默认情况下使用参数--no-setuptools和wheel

GET-PIP.PY警告

根据友好的错误消息WARNING: pip is being invoked by an old script wrapper. This will fail in a future version of pip. Please see https://github.com/pypa/pip/issues/5599 for advice on fixing the underlying issue. To avoid this problem you can invoke Python with '-m pip' instead of running pip directly.，可以将上面的第3点替换为：

bin/python3 -m pip install -U pip [setuptools] [wheel] [--no-cache-dir]

Answer 3

安装新版本的pip可以解决这个问题：

curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
python get-pip.py