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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 _concatenate_shape(input_shape, axis=-1):
 # pylint: disable=invalid-name """Helper to determine the shape of Concatenate output."""

  ax = axis % len(input_shape[0])
  concat_size = sum(shape[ax] for shape in input_shape)
  out_shape = input_shape[0][:ax] + (concat_size,) + input_shape[0][ax+1:]
  return out_shape