code: def length_squared(x, keep_dims=False, name=None, reduction_dim=None):
    
    with tf.name_scope(name, 'length_squared', [x]) as scope:
      x = tf.convert_to_tensor(x, name='x')
      if not reduction_dim:
        reduction_dim = _last_index(x, 1)
      return tf.reduce_sum(
          tf.square(x),
          reduction_dim,
          keep_dims=keep_dims,
          name=scope)
docs: Computes the squared length of x.
  
    Args:
      x: A tensor.
      keep_dims: If true, reduction does not change the rank of the input.
      name: Optional name for this op.
      reduction_dim: The dimension to reduce, by default choose the last one
        and if no shape is specified guess 1.
    Returns:
      The squared length of x.