code: def registerCanvas(self, canvas, name):
      n2 = name
      i = 0
      while n2 in self.canvases:
          n2 = "%s_%03d" % (name, i)
          i += 1
      self.canvases[n2] = canvas
      self.sigCanvasListChanged.emit()
      return n2
  
file_path: pyqtgraph/pyqtgraph/canvas/CanvasManager.py
imports: from ..Qt import QtCore, QtWidgets
  import weakref
label_desc: Use image node_id 3 for calling the CanvasManager obj's underlying member method code with example usage: obj.registerCanvas(canvas, name) and returns: n2