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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 regions():
 """ Get all available regions for the CloudWatch service. :rtype: list :return: A list of :class:`boto.RegionInfo` instances """

    regions = []
    for region_name in RegionData:
        region = RegionInfo(name=region_name,
                            endpoint=RegionData[region_name],
                            connection_cls=CloudWatchConnection)
        regions.append(region)
    return regions