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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 SDB service. :rtype: list :return: A list of :class:`boto.sdb.regioninfo.RegionInfo` instances """

    return [SDBRegionInfo(name='us-east-1',
                          endpoint='sdb.amazonaws.com'),
            SDBRegionInfo(name='eu-west-1',
                          endpoint='sdb.eu-west-1.amazonaws.com'),
            SDBRegionInfo(name='us-west-1',
                          endpoint='sdb.us-west-1.amazonaws.com'),
            SDBRegionInfo(name='sa-east-1',
                          endpoint='sdb.sa-east-1.amazonaws.com'),
            SDBRegionInfo(name='us-west-2',
                          endpoint='sdb.us-west-2.amazonaws.com'),
            SDBRegionInfo(name='ap-northeast-1',
                          endpoint='sdb.ap-northeast-1.amazonaws.com'),
            SDBRegionInfo(name='ap-southeast-1',
                          endpoint='sdb.ap-southeast-1.amazonaws.com')
            ]