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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 create_scheduled_group_action(self, as_group, name, time, desired_capacity=None, min_size=None, max_size=None):
 """ Creates a scheduled scaling action for a Auto Scaling group. If you leave a parameter unspecified, the corresponding value remains unchanged in the affected Auto Scaling group. :type as_group: string :param as_group: The auto scaling group to get activities on. :type name: string :param name: Scheduled action name. :type time: datetime.datetime :param time: The time for this action to start. :type desired_capacity: int :param desired_capacity: The number of EC2 instances that should be running in this group. :type min_size: int :param min_size: The minimum size for the new auto scaling group. :type max_size: int :param max_size: The minimum size for the new auto scaling group. """

        params = {'AutoScalingGroupName': as_group,
                  'ScheduledActionName': name,
                  'Time': time.isoformat()}
        if desired_capacity is not None:
            params['DesiredCapacity'] = desired_capacity
        if min_size is not None:
            params['MinSize'] = min_size
        if max_size is not None:
            params['MaxSize'] = max_size
        return self.get_status('PutScheduledUpdateGroupAction', params)