How to get the enumeration's annotation ?

Is it possible to use schema API  for  retrieving the enumeration's
annotation ?(see below)
How to do it ?

<xsd:simpleType name="TestType">
        <xsd:restriction base="xsd:string">
                <xsd:enumeration value="A">
                        <xsd:annotation>
                                <xsd:appinfo>
                                        <DataType>string</DataType>
                                        <Explanation>XXX</Explanation>

                                </xsd:appinfo>
                        </xsd:annotation>
                </xsd:enumeration>
        </xsd:restriction>
</xsd:simpleType>


Thanks,

Jing