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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(self):
 """Method that saves configuration parameter changes from instance of SHConfig class to global config class and to `config.json` file. Example of use case ``my_config = SHConfig()`` \n ``my_config.instance_id = '<new instance id>'`` \n ``my_config.save()`` """

        is_changed = False
        for prop in self._instance.CONFIG_PARAMS:
            if getattr(self, prop) != getattr(self._instance, prop):
                is_changed = True
                setattr(self._instance, prop, getattr(self, prop))
        if is_changed:
            self._instance.save_configuration()