def METHOD_NAME(self, gpxfile, activity):
    """ Function to transform a Garmin Training Center v2 Track to a valid GPX+ file
    """
    xslt_doc = etree.parse(self.data_path+"/translate_garmintcxv1.xsl")
    transform = etree.XSLT(xslt_doc)
    #xml_doc = etree.parse(filename)
    xml_doc = activity
    result_tree = transform(xml_doc)
    result_tree.write(gpxfile, xml_declaration=True, encoding='UTF-8')