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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 _expand_to_beam_size(tensor, beam_size):
 """Tiles a given tensor by beam_size. Args: beam_size: How much to tile the tensor by. Returns: """

  tensor = tf.expand_dims(tensor, axis=1)
  tile_dims = [1] * tensor.shape.ndims
  tile_dims[1] = beam_size

  return tf.tile(tensor, tile_dims)