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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 addCategory(self, categoryUri, weight):
 """ add a relevant category to the topic page @param categoryUri: uri of the category to be added @param weight: importance of the provided category (typically in range 1 - 50) """

        assert isinstance(weight, (float, int)), "weight value has to be a positive or negative integer"
        self.topicPage["categories"].append({"uri": categoryUri, "wgt": weight})