code: def add_reader(
              self,
              fd: IFileLike,
              callback: typing.Callable[[IFileLike], typing.Any],
      ) -> None:
          
          raise NotImplementedError()
docs: Add a file descriptor to the processor and wait for READ.
  
          Args:
              fd (IFileLike): Any obect that exposes a 'fileno' method that
                  returns a valid file descriptor integer.
              callback (typing.Callable[[IFileLike], typing.Any]): A function
                  that consumes the IFileLike object whenever the READ event is
                  fired.