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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 remove_finished_work_units(self, work_spec_name, work_unit_names):
        '''Remove some finished work units.

        If `work_unit_names` is :const:`None` (which must be passed
        explicitly), all finished work units in `work_spec_name` are
        removed; otherwise only the specific named work units will be.

        :param str work_spec_name: name of the work spec
        :param list work_unit_names: names of the work units, or
          :const:`None` for all in `work_spec_name`
        :return: number of work units removed

        '''
        return self._remove_some_work_units(
            work_spec_name, work_unit_names, suffix=_FINISHED)