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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 prepare(self):
 """ Returns an aioxmpp.stanza.Message built from the Message and prepared to be sent. Returns: aioxmpp.stanza.Message: the message prepared to be sent """


        msg = aioxmpp.stanza.Message(
            to=self.to,
            from_=self.sender,
            type_=aioxmpp.MessageType.CHAT,
        )

        msg.body[None] = self.body

        # Send metadata using xep-0004: Data Forms (https://xmpp.org/extensions/xep-0004.html)
        if len(self.metadata):
            data = forms_xso.Data(type_=forms_xso.DataType.FORM)

            for name, value in self.metadata.items():
                data.fields.append(
                    forms_xso.Field(
                        var=name,
                        type_=forms_xso.FieldType.TEXT_SINGLE,
                        values=[value],
                    )
                )

            if self.thread:
                data.fields.append(forms_xso.Field(var="_thread_node",
                                                   type_=forms_xso.FieldType.TEXT_SINGLE,
                                                   values=[self.thread]))

            data.title = SPADE_X_METADATA
            msg.xep0004_data = [data]

        return msg