你如何确定有效的SoapAction？

  <portType name="MyServicePortType">
   <operation name="MyOperation">
      ...
    </operation>
  </portType>
 <binding name="MyServiceBinding" type="tns:MyServicePortType">
    <soap:binding style="document" transport="http://schemas.xmlsoap.org/soap/http"/>
   <operation name="MyOperation">
      <soap:operation soapAction="http://example.com/MyOperation" style="document"/>
      ...
    </operation>
  </binding>
  ...
</definitions>

import requests

url = "http://example.com/MyService"
action = "http://example.com/MyOperation"
headers = {"Content-Type": "text/xml", "SOAPAction": f'"{action}"'}

response = requests.post(url, data=soap_request_body, headers=headers)