Inheriting from Argument() in order to represent an output format of a back-end as a
character string value.
Object of R6Class() representing an output format of a back-end.
Array(), Integer(), EPSGCode(), String(), Number(),
Date(), RasterCube(), VectorCube(), ProcessGraphArgument(),
ProcessGraphParameter(), OutputFormatOptions(), GeoJson(),
Boolean(), DateTime(), Time(), BoundingBox(), Kernel(),
TemporalInterval(), TemporalIntervals(), CollectionId(), OutputFormat(),
AnyOf(), ProjDefinition(), UdfCodeArgument(), UdfRuntimeArgument() and
UdfRuntimeVersionArgument(),TemporalIntervals(), MetadataFilter()