private Integer getSpaces(CodeUnit cu) {
		if (cu.hasProperty(CodeUnit.SPACE_PROPERTY)) {
			try {
				return cu.getIntProperty(CodeUnit.SPACE_PROPERTY);
			}
			catch (NoValueException e) {
				// can't happen
			}
		}
		return null;
	}
@see ghidra.app.util.viewer.field.FieldFactory#getField(ProxyObj, int)
Ghidra/Features/Base/src/main/java/ghidra/app/util/viewer/field/SpaceFieldFactory.java