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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(self, index, doc_type, id, fields=None, model=None, **query_params):
 """ Get a typed JSON document from an index based on its id. """

        path = make_path(index, doc_type, id)
        if fields is not None:
            query_params["fields"] = ",".join(fields)
        model = model or self.model
        return model(self, self._send_request('GET', path, params=query_params))