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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 addConcept(self, conceptUri, weight, label = None, conceptType = None):
 """ add a relevant concept to the topic page @param conceptUri: uri of the concept to be added @param weight: importance of the provided concept (typically in range 1 - 50) """

        assert isinstance(weight, (float, int)), "weight value has to be a positive or negative integer"
        concept = {"uri": conceptUri, "wgt": weight}
        if label != None: concept["label"] = label
        if conceptType != None: concept["type"] = conceptType
        self.topicPage["concepts"].append(concept)