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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 _put_input(self, input_source: str) -> None: """Put input string to ffmpeg command."""

        input_cmd = shlex.split(str(input_source))
        if len(input_cmd) > 1:
            self._argv.extend(input_cmd)
        else:
            self._argv.extend(["-i", input_source])