You can use the <any/> tag to set global elements to a complex type.
An occurrence of the any tag makes the DataObject Type isOpen() method and the isSequenced() method return true. If the value for maxOccurs is > 1 on an any tag, it has no effect on the structure of the DataObject; it is only used as information during validation. Similarly, the occurrence of multiple any tags in a type does not change the structure of the DataObject; they are used only for validating the location of open data that was set.