This element is an instance of the primitive xsd:duration simple type to
enable use of the ISO 8601 syntax for temporal length (e.g. P5DT4H30M).
It is a valid subtype of TimeDurationType according to section 3.14.6,
rule 2.2.4 in XML Schema, Part 1.
<element name="duration" type="duration"><annotation><documentation xml:lang="en">This element is an instance of the primitive xsd:duration simple type to enable use of the ISO 8601 syntax for temporal length (e.g. P5DT4H30M). It is a valid subtype of TimeDurationType according to section 3.14.6, rule 2.2.4 in XML Schema, Part 1.</documentation></annotation></element>