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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 serialize_to_transport(self, encoding='utf-8', xslt_url=None):
 """Serialize to XML ``bytes`` with prolog. Args: encoding: str Encoding to use for XML doc bytes xslt_url: str If specified, add a processing instruction to the XML doc that specifies the download location for an XSLT stylesheet. Returns: bytes: XML holding a DataONEError based type. """

        assert encoding in ('utf-8', 'UTF-8')
        dataone_exception_pyxb = self.get_pyxb()
        return d1_common.xml.serialize_for_transport(
            dataone_exception_pyxb, xslt_url=xslt_url
        )