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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 _merge_json(self, stmt_json, ev_counts):
 """Merge these statement jsons with new jsons."""

        # Where there is overlap, there _should_ be agreement.
        self.__evidence_counts.update(ev_counts)

        for k, sj in stmt_json.items():
            if k not in self.__statement_jsons:
                self.__statement_jsons[k] = sj  # This should be most of them
            else:
                # This should only happen rarely.
                for evj in sj['evidence']:
                    self.__statement_jsons[k]['evidence'].append(evj)

        if not self.__started:
            self.statements_sample = stmts_from_json(
                self.__statement_jsons.values())
            self.__started = True
        return