class_docstr: Unit tests for the UploadStats class.
class_docstr_tok: ["Unit","tests","for","the","UploadStats","class","."]
code: def testAddScalar(self):
      stats = upload_tracker.UploadStats()
      stats.add_scalars(1234)
      self.assertEqual(stats.num_scalars, 1234)
      stats.add_scalars(4321)
      self.assertEqual(stats.num_scalars, 5555)
  
imports: import sys
  from unittest import mock
  from tensorboard import test
  from tensorboard.uploader import upload_tracker
label_desc: Use image node_id 1 for calling the UploadStatsTest obj's underlying member method code with example usage: obj.testAddScalar() without return types