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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 parse_alarm(self, global_params, region, alarm):
 """ Parse a single CloudWatch trail :param global_params: Parameters shared for all regions :param region: Name of the AWS region :param alarm: Alarm """

        alarm['arn'] = alarm.pop('AlarmArn')
        alarm['name'] = alarm.pop('AlarmName')
        # Drop some data
        for k in ['AlarmConfigurationUpdatedTimestamp', 'StateReason', 'StateReasonData', 'StateUpdatedTimestamp']:
            foo = alarm.pop(k) if k in alarm else None
        alarm_id = self.get_non_aws_id(alarm['arn'])
        self.alarms[alarm_id] = alarm