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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 _get_mods(evt):
 """Helper to extract list of mods from event"""

    mods = []
    mods += [keys.CONTROL] if evt.ControlDown() else []
    mods += [keys.ALT] if evt.AltDown() else []
    mods += [keys.SHIFT] if evt.ShiftDown() else []
    mods += [keys.META] if evt.MetaDown() else []
    return mods