How to install pip and a python package for self installed python?

1. /usr/bin/python points to /usr/bin/python2.7, the old version 2.7.6 python used by my OS 14.04.

   For the old python, I wanted to install module regex:

   $ sudo python -m pip install regex
   /usr/bin/python: No module named pip
   

   So in synatpic, I installed python-pip for the old python. The above command now said:

   Python2/_regex.c:46:20: fatal error: Python.h: No such file or directory
   

   So In synaptic, I installed libpython2.7-dev. Now all works.

2. I also installed a newer version 2.7.9 of Python to /usr/bin/local/python2.7, by compiling its source.

   How can I install pip and then install regex for my new python?

THanks.

Solution 1:

If you install it from source you need to run:

/usr/local/bin/python2.7 -m ensurepip

This will actually install the pip application into /usr/local/bin.

Solution 2:

Python 2.7.9 and later (on the python2 series), and Python 3.4 and later include pip by default 1, so you may have pip already.

To install pip, securely download get-pip.py
Then run the following (which may require administrator access):
python get-pip.py

Source: https://pip.pypa.io/en/latest/installing.html