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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 set_expected_update_frequency(self, update_frequency):
 # type: (str) -> None """Set expected update frequency Args: update_frequency (str):
 Update frequency Returns: None """

        try:
            int(update_frequency)
        except ValueError:
            update_frequency = Dataset.transform_update_frequency(update_frequency)
        if not update_frequency:
            raise HDXError('Invalid update frequency supplied!')
        self.data['data_update_frequency'] = update_frequency