code: def __str__(self):
      return "\n".join(
          str(n)
          for _, n in sorted(
              (n.func_lineno, n) for n in self.nodes.values()
          )
      )
  
imports: import inspect
  import ast
  import re
label_desc: Use image node_id 8 for calling the FlowGraph obj's underlying member method code with example usage: obj.__str__() and returns: str