**Note**: The [PanopticSegmentationGenerator](https://github.com/tensorflow/models/blob/ac7f9e7f2d0508913947242bad3e23ef7cae5a43/official/vision/beta/projects/panoptic_maskrcnn/modeling/layers/panoptic_segmentation_generator.py#L22) layer uses dynamic shapes and hence generating panoptic masks is not supported on Cloud TPUs. Running evaluation on Cloud TPUs is not supported for the same reson.