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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 soap_fault(message=None, actor=None, code=None, detail=None):
 """ Create a SOAP Fault message :param message: Human readable error message :param actor: Who discovered the error :param code: Error code :param detail: More specific error message :return: A SOAP Fault message as a string """

    _string = _actor = _code = _detail = None

    if message:
        _string = soapenv.Fault_faultstring(text=message)
    if actor:
        _actor = soapenv.Fault_faultactor(text=actor)
    if code:
        _code = soapenv.Fault_faultcode(text=code)
    if detail:
        _detail = soapenv.Fault_detail(text=detail)

    fault = soapenv.Fault(
        faultcode=_code,
        faultstring=_string,
        faultactor=_actor,
        detail=_detail,
    )

    return "%s" % fault