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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 get_children(self,node):
 """ Find all the children of a node. must be a undirectional graph with no cycles :param node: :type node: Node :returns: list of nodes :rtype: Node[] """

    if self.find_cycle() or self.__directionless:
      sys.stderr.write("ERROR: do cannot find a branch when there are cycles in the graph\n")
      sys.exit()
    v = self.__get_children(node.id)
    return [self.__nodes[i] for i in v]