'Return a list of rank expressions defined for this domain.
:return: list of ExpressionStatus objects
:rtype: list of :class:`boto.cloudsearch2.option.ExpressionStatus`
object'

def get_expressions(self, names=None):

    fn = self.layer1.describe_expressions
    data = fn(self.name, names)
    data = data['DescribeExpressionsResponse']['DescribeExpressionsResult']['Expressions']
    return [ExpressionStatus(self, d, fn) for d in data]
