class_docstr: A `Callback` to handle the display of progress bars
class_docstr_tok: ["A","`","Callback","`","to","handle","the","display","of","progress","bars"]
code: def _launch_pbar(self):
      self.pbar = progress_bar(
          self.dl, parent=getattr(self, "mbar", None), leave=False
      )
      self.pbar.update(0)
  
imports: from __future__ import annotations
  from ..basics import *
label_desc: Use image node_id 8 for calling the ProgressCallback obj's underlying member method code with example usage: obj._launch_pbar() without return types