code: def isNodeClass(cls):
      try:
          if not issubclass(cls, Node):
              return False
      except:
          return False
      return hasattr(cls, "nodeName")
  
file_path: pyqtgraph/pyqtgraph/flowchart/NodeLibrary.py
imports: from collections import OrderedDict
  from .Node import Node
label_desc: Use image node_id 1 for calling a global function with example usage: isNodeClass(cls) and returns: hasattr, False, False