linux centos 6.7 pip3 install

First Option:

Pip is part of Extra Packages for Enterprise Linux (EPEL), which is a community repository of non-standard packages for the RHEL distribution

rpm -iUvh http://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-5.noarch.rpm

Second Option:

We can also use curl and python to download and install Pip;

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

Then,

python get-pip.py

Just check by typing: pip -V

For reference check here

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