Validate the user specified regions are valid
        :return:

def validate_regions(self):
        """
        Validate the user specified regions are valid
        :return:
        """
        for region in self.aws_regions:
            if region not in aws_regions:
                print "Error: Specified region: {} is not a valid aws_region".format(region)
                print "Valid regions are: {}".format(aws_regions)