错误信息：
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Failed building wheel for cryptography
Command "/usr/bin/python3 -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-kqw5sdzp/cryptography/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-w4uldwqk-record/install-record.txt --single-version-externally-managed --compile --user --prefix=" failed with error code 1 in /tmp/pip-build-kqw5sdzp/cryptography/
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执行下面的命令，下面的包按需要安装，一般是缺少libssl-dev
我就是只安装了libssl-dev这个就可以了
sudo apt-get install build-essential libssl-dev libffi-dev python-dev python3-dev