How to use the markovify.chain.Chain.from_json function in markovify

def from_chain(cls, chain_json, corpus=None, parsed_sentences=None):
        """
        Init a Text class based on an existing chain JSON string or object
        If corpus is None, overlap checking won't work.
        """
        chain = Chain.from_json(chain_json)
        return cls(corpus or None, parsed_sentences=parsed_sentences, state_size=chain.state_size, chain=chain)

raise ValueError("All `models` must be of the same type.")

    c = {}

    for m, w in zip(model_dicts, weights):
        for state, options in m.items():
            current = c.get(state, {})
            for subseq_k, subseq_v in options.items():
                subseq_prev = current.get(subseq_k, 0)
                current[subseq_k] = subseq_prev + (subseq_v * w)
            c[state] = current

    ret_inst = models[0]

    if isinstance(ret_inst, Chain):
        return Chain.from_json(c)
    if isinstance(ret_inst, Text):
        if any(m.retain_original for m in models):
            combined_sentences = []
            for m in models:
                if m.retain_original:
                    combined_sentences += m.parsed_sentences
            return ret_inst.from_chain(c, parsed_sentences=combined_sentences)
        else:
            return ret_inst.from_chain(c)
    if isinstance(ret_inst, list):
        return list(c.items())
    if isinstance(ret_inst, dict):
        return c

def from_dict(cls, obj, **kwargs):
        return cls(
            None,
            state_size=obj["state_size"],
            chain=Chain.from_json(obj["chain"]),
            parsed_sentences=obj.get("parsed_sentences")
        )