code: def test__setitem__adds_new_str_query_param(self):
      assert "test" not in self.query_params
      self.query_params["test"] = "test"
      assert self.query_params.get("test") == "test"
      message = self.get_message_from_queue(0)
      assert "test=test" in message.page_info_changed.query_string
  
imports: import pytest
  from streamlit.errors import StreamlitAPIException
  from streamlit.runtime.state.query_params import QueryParams
  from tests.delta_generator_test_case import DeltaGeneratorTestCase
label_desc: Use image node_id 10 for calling the QueryParamsMethodTests obj's underlying member method code with example usage: obj.test__setitem__adds_new_str_query_param() without return types