Windows 10, Windows 7 如果pip install在CMD提示符下不工作，使用Anaconda提示符运行它-它工作。

https://github.com/pypa/virtualenv/issues/1139

Windows 10 如果你想在正常的cmd中使用pip，而不仅仅是在Anaconda提示符中。您需要添加3个环境路径。 比如:

D:\Anaconda3 
D:\Anaconda3\Scripts
D:\Anaconda3\Library\bin 

大多数人只添加D:\Anaconda3\Scripts

你可以尝试brew链接，它会告诉你正确的说明:

$ brew link openssl --force
Warning: Refusing to link macOS provided/shadowed software: openssl@1.1
If you need to have openssl@1.1 first in your PATH run:
  echo 'export PATH="/usr/local/opt/openssl@1.1/bin:$PATH"' >> ~/.zshrc

For compilers to find openssl@1.1 you may need to set:
  export LDFLAGS="-L/usr/local/opt/openssl@1.1/lib"
  export CPPFLAGS="-I/usr/local/opt/openssl@1.1/include"

For pkg-config to find openssl@1.1 you may need to set:
  export PKG_CONFIG_PATH="/usr/local/opt/openssl@1.1/lib/pkgconfig"

对于未来试图解决这个问题的Oracle Linux用户，下面是对我有用的方法。 首先安装缺少的库:

yum install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel 
readline-devel tk-devel gdbm-devel db4-devel libpcap-devel xz-devel

然后cd到Python3。X库并运行:

make
make install 

苹果操作系统

我在Mac OS(Mojave)上遇到了同样的问题，并解决了这个链接中提到的问题- Openssl问题。

如果你没有Homebrew或不知道什么是Homebrew:

/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

或者如果你已经安装了Homebrew:

brew update && brew upgrade
brew uninstall --ignore-dependencies openssl; brew install https://github.com/tebelorg/Tump/releases/download/v1.0.0/openssl.rb

更新: 请记住，我必须使用——ignore-dependencies标记，因为安装的其他包依赖于OpenSSL。

另外，如果问题是在使用pyenv后引起的，您可以通过使用以下方法修复:

brew reinstall python

我得到了同样的错误:

WARNING: pip is configured with locations that require TLS/SSL, however the ssl module in Python is not available.
WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pb-tool/
WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pb-tool/
ERROR: Operation cancelled by user
WARNING: pip is configured with locations that require TLS/SSL, however the ssl module in Python is not available.
Could not fetch URL https://pypi.org/simple/pip/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/pip/ (Caused by SSLError("Can't connect to HTTPS URL because the SSL module is not available.")) - skipping

在《Anaconda》中，我使用了以下命令:

conda install anaconda-navigator

本文中提到:pip配置了需要TLS/SSL的位置，但是Python中的SSL模块不可用