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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 GetOutputDir(self, base_dir, config_filename):
 """Add the repack config filename onto the base output directory. This allows us to repack lots of different configs to the same installer name and still be able to distinguish them. Args: base_dir: output directory string config_filename: the secondary config filename string Returns: String to be used as output directory for this repack. """

    return os.path.join(base_dir,
                        os.path.basename(config_filename.replace(".yaml", "")))