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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 find_callback(args, kw=None):
    'Return callback whether passed as a last argument or as a keyword'
    if args and callable(args[-1]):
        return args[-1], args[:-1]
    try:
        return kw['callback'], args
    except (KeyError, TypeError):
        return None, args