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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 configToJson(self, fileName):
 """Save the configuration of the city in a JSON. :param fileName: path to the output file. :type fileName: str. """

        config = self.getConfig()
        with open(fileName, "w") as outfile:
            dump(config, outfile, indent=4, sort_keys=True)