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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 clearData(self, type: str = '') -> None: """Remove data of type foramt. If type argument is omitted, remove all data. """

        type = normalize_type(type)
        if not type:
            self.__data.clear()
        elif type in self.__data:
            del self.__data[type]