code: def _start(self):
          
          error = None
          output = None
  
          try:
              output = self.func(*self.args, **self.kwargs)
          except Exception as err:
              error = err
  
          if not self._is_finished:
              self.sig_finished.emit(self, output, error)
          self._is_finished = True
docs: Start process worker for given method args and kwargs.