code: def test_POST(self):
      url = "abc"
      data = {"foo": "bar"}
      self.assertEqual(self.rnw.POST(url, data), "json")
      self.rnw.session.post.assert_called_once_with(
          url,
          data=json.dumps(data),
          headers={"content-type": "application/json"},
          timeout=None,
          auth=None,
      )
  
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 8 for calling the TestRequestsNetworkWrapper obj's underlying member method code with example usage: obj.test_POST() without return types