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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 _arg2opt(arg):
    '''
    Turn a pass argument into the correct option
    '''
    res = [o for o, a in option_toggles.items() if a == arg]
    res += [o for o, a in option_flags.items() if a == arg]
    return res[0] if res else None