class_docstr: Tests for covid-19 dataset.
class_docstr_tok: ["Tests","for","covid-19","dataset","."]
code: def setUp(self):
      super().setUp()
      covid19._N_RECORDS = 3
      covid19._BATCH_SIZE = 2
  
imports: import tensorflow_datasets.public_api
  from tensorflow_datasets.structured.covid19 import covid19
label_desc: Use image node_id 1 for calling the Covid19Test obj's underlying member method code with example usage: obj.setUp() without return types