code: def testBetween1KAnd1M(self):
      self.assertEqual(
          upload_tracker.readable_bytes_string(1337), "1.3 kB"
      )
  
imports: import sys
  from unittest import mock
  from tensorboard import test
  from tensorboard.uploader import upload_tracker
label_desc: Use image node_id 3 for calling the ReadableBytesStringTest obj's underlying member method code with example usage: obj.testBetween1KAnd1M() without return types