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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 match_config(regex):
    '''
    Display the current values of all configuration variables whose
    names match the given regular expression.

    .. versionadded:: 2016.11.0

    .. code-block:: bash

        salt '*' trafficserver.match_config regex
    '''
    if _TRAFFICCTL:
        cmd = _traffic_ctl('config', 'match', regex)
    else:
        cmd = _traffic_line('-m', regex)

    return _subprocess(cmd)