def shapes(tensors):
    """Get the static shapes of tensors in a list.

    Arguments:
      tensors: an iterable of `tf.Tensor`.

    Returns:
      a `list` of `tf.TensorShape`, one for each tensor in `tensors`,
        representing their static shape (via `tf.Tensor.get_shape()`).
    """
    return [t.get_shape() for t in tensors]