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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 update_stage_config( self, project_name, stage_name, cloudwatch_log_level, cloudwatch_data_trace, cloudwatch_metrics_enabled ):
 """ Update CloudWatch metrics configuration. """

        if cloudwatch_log_level not in self.cloudwatch_log_levels:
            cloudwatch_log_level = 'OFF'

        for api in self.get_rest_apis(project_name):
            self.apigateway_client.update_stage(
                restApiId=api['id'],
                stageName=stage_name,
                patchOperations=[
                    self.get_patch_op('logging/loglevel', cloudwatch_log_level),
                    self.get_patch_op('logging/dataTrace', cloudwatch_data_trace),
                    self.get_patch_op('metrics/enabled', cloudwatch_metrics_enabled),
                ]
            )