how to update pip freeze code example

Example 1: how to update pip python

python -m pip install --upgrade pip

Example 2: how to update pip

#for updating pip type the following command in terminal or cmd or powershell
python -m pip install --upgrade pip

Example 3: python update installed packages

py2
$ pip install pip-review

$ pip-review --local --interactive

py3
$ pip3 install pip-review

$ py -3 -m pip_review --local --interactive

Example 4: update all modules python in cmd

import pkg_resources
from subprocess import call

packages = [dist.project_name for dist in pkg_resources.working_set]
call("pip install --upgrade " + ' '.join(packages), shell=True)