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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 save_instances(self, path, binary=False, mode=SaveMode.LOCAL_SAVE):
 """Save the instances in the system to the specified file. If binary is True, the instances will be saved in binary format. The Python equivalent of the CLIPS save-instances command. """

        if binary:
            ret = lib.EnvBinarySaveInstances(self._env, path.encode(), mode)
        else:
            ret = lib.EnvSaveInstances(self._env, path.encode(), mode)
        if ret == 0:
            raise CLIPSError(self._env)

        return ret