code: def test_POST_with_credentials(self):
      self._test_METHOD_with_credentials(
          self.rnw.POST,
          self.rnw.session.post,
          headers={"content-type": "application/json"},
          data=True,
          response="json",
      )
  
imports: import json
  import requests
  from requests.auth import HTTPBasicAuth
  from tabpy.tabpy_tools.rest import RequestsNetworkWrapper, ServiceClient
  import unittest
  from unittest.mock import Mock
label_desc: Use image node_id 20 for calling the TestRequestsNetworkWrapper obj's underlying member method code with example usage: obj.test_POST_with_credentials() without return types