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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 stage_subset(self, *files_to_add: str):
 """ Stages a subset of files :param files_to_add: files to stage :type files_to_add: str """

        LOGGER.info('staging files: %s', files_to_add)
        self.repo.git.add(*files_to_add, A=True)