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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 _parse_example_spec(self):
 """Returns a `tf.Example` parsing spec as dict."""

    height, width = image_util.get_expected_image_size(self.module_spec)
    input_shape = [height, width, 3]
    return {self.key: tf_v1.FixedLenFeature(input_shape, tf.float32)}