class_docstr: Asynchronous result.
docstr: Return whether the call completed without raising an exception.
  
  If the result is not ready then raise `ValueError`.
docstr_tok: ["Return","whether","the","call","completed","without","raising","an","exception",".","If","the","result","is","not","ready","then","raise","`","ValueError","`","."]
code: def successful(self):
      """Return whether the call completed without raising an exception.
  
      If the result is not ready then raise `ValueError`.
  
      """
      if not self.ready():
          raise ValueError(f"{self!r} not ready")
      try:
          return self.future.exception() is None
      except _futures.CancelledError:
          return False
  
imports: from os import cpu_count
  import functools
  import operator
  import threading
  import warnings
  import weakref
  from ..None import futures
label_desc: Use image node_id 5 for calling the AsyncResult obj's underlying member method code with example usage: obj.successful() and returns: unknown, False