@NotNull
  public static ControlFlow getControlFlow(@NotNull ScopeOwner element,
                                           @NotNull PyControlFlowBuilder controlFlowBuilder) {
    SoftReference<ControlFlow> ref = element.getUserData(CONTROL_FLOW_KEY);
    ControlFlow flow = dereference(ref);
    if (flow == null) {
      flow = controlFlowBuilder.buildControlFlow(element);
      element.putUserData(CONTROL_FLOW_KEY, new SoftReference<>(flow));
    }
    return flow;
  }
@NotNull
  public static ControlFlow getControlFlow(@NotNull ScopeOwner element,
                                           @NotNull PyControlFlowBuilder controlFlowBuilder)