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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 init(size=250):
 """Initialize mpv."""

    player = mpv.MPV(start_event_thread=False)
    player["force-window"] = "immediate"
    player["keep-open"] = "yes"
    player["geometry"] = f"{size}x{size}"
    player["autofit"] = f"{size}x{size}"
    player["title"] = "bum"

    return player