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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 _merge_filters(self) -> None: """Merge all filter config in command line."""

        for opts in (["-filter:a", "-af"], ["-filter:v", "-vf"]):
            filter_list = []
            new_argv = []
            cmd_iter = iter(self._argv)
            for element in cmd_iter:
                if element in opts:
                    filter_list.insert(0, next(cmd_iter))
                else:
                    new_argv.append(element)

            # update argv if changes
            if filter_list:
                new_argv.extend([opts[0], ",".join(filter_list)])
                self._argv = new_argv.copy()