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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 dynamodb_autoscaling_policy(tables):
 """Policy to allow AutoScaling a list of DynamoDB tables."""

    return Policy(
        Statement=[
            Statement(
                Effect=Allow,
                Resource=dynamodb_arns(tables),
                Action=[
                    dynamodb.DescribeTable,
                    dynamodb.UpdateTable,
                ]
            ),
            Statement(
                Effect=Allow,
                Resource=['*'],
                Action=[
                    cloudwatch.PutMetricAlarm,
                    cloudwatch.DescribeAlarms,
                    cloudwatch.GetMetricStatistics,
                    cloudwatch.SetAlarmState,
                    cloudwatch.DeleteAlarms,
                ]
            ),
        ]
    )