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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_batch_coordinates(bc, length_factor):
 """Duplicate elements of bc by length_factor. Args: bc (tf.Tensor):
 int32 tensor of shape [1, length, 1] length_factor (int):
 Returns: tf.Tensor: of shape [1, length*length_factor, 1] where every elements has been duplicated length_factor times. """

  assert bc.get_shape().as_list() == [1, None, 1]
  # bc has shape [1, length, 1]
  bc *= tf.constant([[1] * length_factor])
  # bc has shape [1, length, length_factor]
  bc = tf.reshape(bc, [1, -1, 1])
  # bc has shape [1, length*length_factor]
  return bc