Package management system Pip

Pip will be used to install Python packages. It is a package management system used to install packages from Python Package Index (Pypi). Most likely, if you already have Python installed, pip is installed.

Check pip version:

$ pip --version
pip 19.1.1 from /home/vagrant/venv/pyneng-py3-7/lib/python3.7/site-packages/pip (python 3.7)

If command failed, pip is not installed. Pip installation is described in documentation

Module installation

Command to install modules pip install:

$ pip install tabulate

To delete package:

$ pip uninstall tabulate

In addition, it is sometimes necessary to update package:

$ pip install --upgrade tabulate

pip or pip3

Depending on how Python is installed and configured in system it may be necessary to use pip3 instead of pip. To check which option is used, you should execute command pip --version.

A version where pip corresponds to Python 2.7:

$ pip --version
pip 9.0.1 from /usr/local/lib/python2.7/dist-packages (python 2.7)

A version where pip3 corresponds to 3.7:

$ pip3 --version
pip 19.1.1 from /home/vagrant/venv/pyneng-py3-7/lib/python3.7/site-packages/pip (python 3.7)

If system uses pip3, then every time a Python module is installed in book it will be necessary to replace pip with pip3.

Alternatively, call pip:

$ python3.7 -m pip install tabulate

Thus, it is always clear for which version of Python the package is installed.