class_docstr: Represents a qualified name.
code: def __str__(self):
      root = self.qn[0]
      if self.has_subscript():
          return "{}[{}]".format(root, self.qn[1])
      if self.has_attr():
          return ".".join(map(str, self.qn))
      else:
          return str(root)
  
imports: import collections
  import gast
  from tensorflow.python.autograph.pyct import anno
  from tensorflow.python.autograph.pyct import parser
label_desc: Use image node_id 15 for calling the QN obj's underlying member method code with example usage: obj.__str__() and returns: str, str, str