sh is a full-fledged subprocess replacement for Python 2.6 - 3.5, PyPy and PyPy3 that allows you to call any program as if it were a function:

from sh import ifconfig
print ifconfig("eth0")

sh is not a collection of system commands implemented in Python.

$> pip install sh

First install the development requirements:

$> pip install -r requirements-dev.txt

The run the tests for all Python versions on your system:

$> python sh.py test

To run a single test for all environments:

$> python sh.py test FunctionalTests.test_unicode_arg

To run a single test for a single environment:

$> python sh.py test -e 3.4 FunctionalTests.test_unicode_arg

First run all of the tests:

$> python sh.py test

This will aggregate a .coverage. You may then visualize the report with:

$> coverage report

Or generate visual html files with:

$> coverage html

Which will create ./htmlcov/index.html that you may open in a web browser.