class_docstr: QLabel specifically for displaying numerical values.
  Extends QLabel adding some extra functionality:
  
    - displaying units with si prefix
    - built-in exponential averaging
code: def paintEvent(self, ev):
      self.setText(self.generateText())
      return super().paintEvent(ev)
  
file_path: pyqtgraph/pyqtgraph/widgets/ValueLabel.py
imports: from time import perf_counter
  from ..None import functions
  from ..Qt import QtWidgets
label_desc: Use image node_id 6 for calling the ValueLabel obj's underlying member method code with example usage: obj.paintEvent(ev) and returns: super