fetch
Gets the collection of Basemap objects in the portal's developer basemap gallery group.
The portal's developer basemap gallery group is defined by the portal's administrator and contains the basemaps that are displayed in the Map Viewer basemap gallery when a user logs in with an ArcGIS Location Platform account. The basemaps in the collection are not loaded, but you can access their PortalItem metadata from Basemap.item.
Return
A Result that provides Basemap objects within the developer basemap gallery group.