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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 get_time_server():
    '''
    Display the currently set network time server.

    :return: the network time server
    :rtype: str

    CLI Example:

    .. code-block:: bash

        salt '*' timezone.get_time_server
    '''
    ret = salt.utils.mac_utils.execute_return_result(
        'systemsetup -getnetworktimeserver')
    return salt.utils.mac_utils.parse_return(ret)