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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def coverage():
 """Run coverage tests."""

    # Note: coverage options are controlled by .coveragerc file
    install()
    test_setup()
    sh("%s -m coverage run %s" % (PYTHON, TEST_SCRIPT))
    sh("%s -m coverage report" % PYTHON)
    sh("%s -m coverage html" % PYTHON)
    sh("%s -m webbrowser -t htmlcov/index.html" % PYTHON)