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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 _update_sub_file_dict(self, sub_files):
 """Update a file dict with information from self"""

        sub_files.file_dict.clear()
        for job_details in self.jobs.values():
            if job_details.file_dict is not None:
                sub_files.update(job_details.file_dict)
            if job_details.sub_file_dict is not None:
                sub_files.update(job_details.sub_file_dict)