class_docstr: Context manager to defer exceptions from imports.
  
  Catches :exc:`ImportError` and :exc:`SyntaxError`.
  If any exception is caught, this class raises an :exc:`ImportError` when being checked.
class_docstr_tok: ["Context","manager","to","defer","exceptions","from","imports",".","Catches",":","exc",":","`","ImportError","`","and",":","exc",":","`","SyntaxError","`",".","If","any","exception","is","caught",",","this","class","raises","an",":","exc",":","`","ImportError","`","when","being","checked","."]
docstr: Return whether the context manager has caught any exceptions.
  
  Returns:
      :obj:`True` if no exceptions are caught, :obj:`False` otherwise.
docstr_tok: ["Return","whether","the","context","manager","has","caught","any","exceptions",".","Returns",":",":","obj",":","`","True","`","if","no","exceptions","are","caught",",",":","obj",":","`","False","`","otherwise","."]
code: def is_successful(self) -> bool:
      """Return whether the context manager has caught any exceptions.
  
      Returns:
          :obj:`True` if no exceptions are caught, :obj:`False` otherwise.
  
      """
      return self._deferred is None
  
file_path: optuna/optuna/_imports.py
imports: import importlib
  import types
  from types import TracebackType
  from typing import Any
  from typing import Optional
  from typing import Tuple
  from typing import Type
label_desc: Use image node_id 4 for calling the _DeferredImportExceptionContextManager obj's underlying member method code with example usage: obj.is_successful() and returns: unknown