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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 from_xml(cls, xml_bytes):
 """ Create an instance of this from XML bytes. @param xml_bytes: C{str} bytes of XML to parse @return: an instance of L{MultipartInitiationResponse} """

        root = XML(xml_bytes)
        return cls(root.findtext('Bucket'),
                   root.findtext('Key'),
                   root.findtext('UploadId'))