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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 index_of(self, child):
 """ Returns the given child index. Usage:: 0 1 :param child: Child node. :type child: AbstractNode or AbstractCompositeNode or Object :return: Child index. :rtype: int """


        for i, item in enumerate(self.__children):
            if child is item:
                return i