@Override
      public DataSource<IMAGE> get() {
        return getDataSourceForRequest(
            // NULLSAFE_FIXME[Parameter Not Nullable]
            controller, controllerId, imageRequest, callerContext, cacheLevel);
      }
Creates a data source supplier for the given image request.
drawee/src/main/java/com/facebook/drawee/controller/AbstractDraweeControllerBuilder.java