class_docstr: Tracker for uploader progress and status.
class_docstr_tok: ["Tracker","for","uploader","progress","and","status","."]
docstr: Create a context manager for tracking a scalar batch upload.
  
  Args:
    num_scalars: Number of scalars in the batch.
code: def scalars_tracker(self, num_scalars):
      """Create a context manager for tracking a scalar batch upload.
  
      Args:
        num_scalars: Number of scalars in the batch.
      """
      self._overwrite_line_message("Uploading %d scalars" % num_scalars)
      try:
          yield
      finally:
          self._stats.add_scalars(num_scalars)
  
imports: import contextlib
  from datetime import datetime
  import sys
  import time
label_desc: Use image node_id 9 for calling the UploadTracker obj's underlying member method code with example usage: obj.scalars_tracker(num_scalars) without return types