code: def test_uniqueness(self, db_json):
      db = hl.experimental.DB(region="us", cloud="gcp", config=db_json)
      t = hl.utils.genomic_range_table(10)
      t = db.annotate_rows_db(t, "unique_dataset", "nonunique_dataset")
      assert t.unique_dataset.dtype == hl.dtype(
          "struct{annotation: str}"
      )
      assert t.nonunique_dataset.dtype == hl.dtype(
          "array<struct{annotation: str}>"
      )
  
imports: import pytest
  import hail
  from hail.backend.service_backend import ServiceBackend
label_desc: Use image node_id 2 for calling the TestAnnotationDB obj's underlying member method code with example usage: obj.test_uniqueness(db_json) without return types