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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 arg_types(**kwargs):
 """ Mark the expected types of certain arguments. Arguments for which no types are provided default to strings. To specify an argument type, give this decorator a keyword argument, where the argument name is the name of the function argument and the value is a callable taking one argument, which will convert a string to a value of that type. Note that the 'bool' type is treated specially. """


    def decorator(func):
        if not hasattr(func, '_bark_types'):
            func._bark_types = {}
        func._bark_types.update(kwargs)
        return func

    return decorator