code: def query(self, status):
      status.Set_source(self.source)
      status.Set_tag(self.tag)
  
file_path: mpi4py/test/test_grequest.py
imports: from mpi4py import MPI
  import mpiunittest
label_desc: Use image node_id 1 for calling the GReqCtx obj's underlying member method code with example usage: obj.query(status) without return types