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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 str_to_mac(mac_string):
 """Convert a readable string to a MAC address Args: mac_string (str):
 a readable string (e.g. '01:02:03:04:05:06') Returns: str: a MAC address in hex form """

    sp = mac_string.split(':')
    mac_string = ''.join(sp)
    return binascii.unhexlify(mac_string)