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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_decoder(cls, ds, var):
 """ Class method to get the right decoder class that can decode the given dataset and variable Parameters %(CFDecoder.can_decode.parameters)s Returns ------- CFDecoder The decoder for the given dataset that can decode the variable `var`"""

        for decoder_cls in cls._registry:
            if decoder_cls.can_decode(ds, var):
                return decoder_cls(ds)
        return CFDecoder(ds)