'Retrieves the output shape(s) of a layer at a given node.
# Arguments
node_index: Integer, index of the node
from which to retrieve the attribute.
E.g. `node_index=0` will correspond to the
first time the layer was called.
# Returns
A shape tuple
(or list of shape tuples if the layer has multiple outputs).'

def get_output_shape_at(self, node_index):

    return self._get_node_attribute_at_index(node_index, 'output_shapes', 'output    shape')
