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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 addCity(self, fileName):
 """Add a JSON file and read the users. :param fileName: path to the JSON file. This file has to have a list of users, called users. :type fileName: str. """

        with open(fileName) as data_file:
            data = load(data_file)
        for u in data["users"]:
            if not any(d["name"] == u["name"] for d in self.__users):
                self.__users.append(u)