install
http://pip.readthedocs.org/en/latest/installing.html
To install or upgrade pip, securely download get-pip.py
$ python get-pip.py
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pip 是easy_install的替代品,相对于easy_install,pip可以卸载、升级软件包。管理python包时都应该使用pip而不是easy_install。
pip install pymongo
pip install pymongo==1.10.1
pip install --upgrade pymongo