code: def _get_reference_namespace(self, name):
          
          glbs = self._mglobals()
          if self._pdb_frame is None:
              return glbs
          else:
              lcls = self._pdb_locals
              if name in lcls:
                  return lcls
              else:
                  return glbs
docs: Return namespace where reference name is defined
  
          It returns the globals() if reference has not yet been defined