def validate_graph_colors(graph):
	"""
	Validates that each graph node has a color distinct from the colors of its neighbors.
	:param graph: the graph to examine
	:return: boolean indicating whether the graph nodes have valid colors
	"""
	for graph_node in graph:
		print(graph_node.color + ': ' + ', '.join(str(o.color) for o in graph_node.neighbors))
		if graph_node.color in (o.color for o in graph_node.neighbors):
			return False
	return True