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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def extra_reading_spec(self):
 """Additional data fields to store on disk and their decoders."""

    field_names = ("frame_number", "action", "reward", "done")
    data_fields = {
        name: tf.FixedLenFeature([1], tf.int64) for name in field_names
    }
    decoders = {
        name: tf.contrib.slim.tfexample_decoder.Tensor(tensor_key=name)
        for name in field_names
    }
    return (data_fields, decoders)