code: def _execute(self,
                   command,        # type: str
                   args,           # type: List[str]
                   env_vars=None,  # type: EnvVars
                   shim=None       # type: OptStr
                   ):
          # type: (...) -> Tuple[int, bytes, bytes]
          
          main_args = [command] + args
          logger.debug("calling pip %s", ' '.join(main_args))
          rc, out, err = self._wrapped_pip.main(main_args, env_vars=env_vars,
                                                shim=shim)
          return rc, out, err
docs: Execute a pip command with the given arguments.