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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 parse_client_cert_pair(config_value):
 """Parses the client cert pair from config item. :param config_value: the string value of config item. :returns: tuple or none. """

    if not config_value:
        return
    client_cert = config_value.split(':')
    if len(client_cert) != 2:
        tips = ('client_cert should be formatted like '
                '"/path/to/cert.pem:/path/to/key.pem"')
        raise ValueError('{0!r} is invalid.\n{1}'.format(config_value, tips))
    return tuple(client_cert)