side (SidesSimple)

b2boptic → items → item → pair → frame → shape → explicit

values	description
RIGHT	shape for right lens
LEFT	shape for left lens

<xs:simpleType name="SidesSimple">
  <xs:restriction base="xs:string">
    <xs:enumeration value="RIGHT" />
    <xs:enumeration value="LEFT" />
  </xs:restriction>
</xs:simpleType>