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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(self, msg, name):
 """Parses a simple message :param msg: the json-decoded value :param name: the requested name :raises UnknownMessageType: if the type is not 'simple' :raises InvalidMessage: if the message cannot be parsed or validated """


        # On requests we imply 'simple' if there is no input message
        if msg is None:
            return

        if not isinstance(msg, string_types):
            raise InvalidMessage("The 'value' attribute is not a string")

        self.name = name
        self.payload = msg
        self.msg_type = 'simple'