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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 mac_addr_info():
 """Returns mac address. """

    mac = get_mac()
    if mac == get_mac():  # not random generated
        hexa = '%012x' % mac
        value = ':'.join(hexa[i:i+2] for i in range(0, 12, 2))
    else:
        value = None
    return {'mac': value}