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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 install_salt_support(from_ppa=True):
 """Installs the salt-minion helper for machine state. By default the salt-minion package is installed from the saltstack PPA. If from_ppa is False you must ensure that the salt-minion package is available in the apt cache. """

    if from_ppa:
        subprocess.check_call([
            '/usr/bin/add-apt-repository',
            '--yes',
            'ppa:saltstack/salt',
        ])
        subprocess.check_call(['/usr/bin/apt-get', 'update'])
    # We install salt-common as salt-minion would run the salt-minion
    # daemon.
    charmhelpers.fetch.apt_install('salt-common')