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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 register_output_name(self, input_folder, rel_name, rel_output_name):
 """Register proper and improper file mappings."""

        self.improper_input_file_mapping[rel_name].add(rel_output_name)
        self.proper_input_file_mapping[os.path.join(input_folder, rel_name)] = rel_output_name
        self.proper_input_file_mapping[rel_output_name] = rel_output_name