python從字符串中操作xml

xmltree_root = ET.fromstring(xml_body)
payload_len = len(injectiondata)
xmldata_len = len(xmltree_root)
try:
    for elem in xmltree_root.iter():
        for payload in injectiondata:
            temp_text = elem.text
            if elem.text == None or elem.text == "None":
                pass
            else:
                elem.text = str(elem.text) + payload
            injection_payload = ET.tostring(xmltree_root)
            injection_payload = injection_payload.decode("utf-8")
            xml_payload_list.append(injection_payload)
            elem.text = temp_text