code: def validate(cls, job_config):
      
      super(SampleInputReader, cls).validate(job_config)
  
      params = job_config.input_reader_params
      # Validate count.
      if cls.COUNT not in params:
        raise errors.BadReaderParamsError("Must specify %s" % cls.COUNT)
      if not isinstance(params[cls.COUNT], int):
        raise errors.BadReaderParamsError("%s should be an int but is %s" %
                                          (cls.COUNT, type(params[cls.COUNT])))
      if params[cls.COUNT] <= 0:
        raise errors.BadReaderParamsError("%s should be a positive int")
      # Validate string length.
      if cls.STRING_LENGTH in params and not (
          isinstance(params[cls.STRING_LENGTH], int) and
          params[cls.STRING_LENGTH] > 0):
        raise errors.BadReaderParamsError("%s should be a positive int "
                                          "but is %s" %
                                          (cls.STRING_LENGTH,
                                           params[cls.STRING_LENGTH]))
docs: Inherit docs.