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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 available():
 """Detect if the FFmpeg backend can be used on this system."""

    proc = popen_multiple(
        COMMANDS,
        ['-version'],
        stdout=subprocess.PIPE,
        stderr=subprocess.PIPE,
        creationflags=PROC_FLAGS,
    )
    proc.wait()
    return (proc.returncode == 0)