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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 from_json(cls, json_thing):
 """ Given a JSON object or JSON string that was created by `self.to_json`, return the corresponding markovify.Chain. """


        if isinstance(json_thing, basestring):
            obj = json.loads(json_thing)
        else:
            obj = json_thing

        if isinstance(obj, list):
            rehydrated = dict((tuple(item[0]), item[1]) for item in obj)
        elif isinstance(obj, dict):
            rehydrated = obj
        else:
            raise ValueError("Object should be dict or list")

        state_size = len(list(rehydrated.keys())[0])

        inst = cls(None, state_size, rehydrated)
        return inst