解决 ImportError: module 'pip' has no attribute 'main'

升级pip10.0.0报错如下：
Traceback (most recent call last):
File “/usr/local/lib/python3.6/site-packages/pkg_resources/init.py”, line 2332, in resolve
return functools.reduce(getattr, self.attrs, module)
AttributeError: module ‘pip’ has no attribute ‘main’

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File “”, line 11, in
load_entry_point(‘pip==9.0.3’, ‘console_scripts’, ‘pip3’)()
File “”, line 480, in load_entry_point
return get_distribution(dist).load_entry_point(group, name)
File “”, line 2693, in load_entry_point
return ep.load()
File “”, line 2324, in load
return self.resolve()
File “”, line 2334, in resolve
raise ImportError(str(exc))
ImportError: module ‘pip’ has no attribute ‘main’

解决方法：

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

Reference：
https://pip.pypa.io/en/stable/installing/