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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 _backup_compresslevel(self, dirs):
 """Create a backup file with a compresslevel parameter."""

        # Only supported in Python 3.7+
        with ZipFile(self.zip_filename, 'w', compresslevel=self.compress_level) as backup_zip:
            for path in tqdm(dirs, desc='Writing Zip Files', total=len(dirs)):
                backup_zip.write(path, path[len(self.source):len(path)])