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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 enable_metrics_collection(self, as_group, granularity, metrics=None):
 """ Enables monitoring of group metrics for the Auto Scaling group specified in AutoScalingGroupName. You can specify the list of enabled metrics with the Metrics parameter. Auto scaling metrics collection can be turned on only if the InstanceMonitoring.Enabled flag, in the Auto Scaling group's launch configuration, is set to true. :type autoscale_group: string :param autoscale_group: The auto scaling group to get activities on. :type granularity: string :param granularity: The granularity to associate with the metrics to collect. Currently, the only legal granularity is "1Minute". :type metrics: string list :param metrics: The list of metrics to collect. If no metrics are specified, all metrics are enabled. """

        params = {'AutoScalingGroupName': as_group,
                  'Granularity': granularity}
        if metrics:
            self.build_list_params(params, metrics, 'Metrics')
        return self.get_status('EnableMetricsCollection', params)