How to use the @truffle/debugger.selectors.session function in @truffle/debugger

txSpinner.succeed();
          //if successful, change prompt
          this.setPrompt(DebugUtils.formatPrompt(this.network, cmdArgs));
        } else {
          txSpinner.fail();
          loadFailed = true;
        }
      } else {
        loadFailed = true;
        this.printer.print(
          "Please unload the current transaction before loading a new one."
        );
      }
    }
    if (cmd === "T") {
      if (this.session.view(selectors.session.status.loaded)) {
        await this.session.unload();
        this.printer.print("Transaction unloaded.");
        this.setPrompt(DebugUtils.formatPrompt(this.network));
      } else {
        this.printer.print("No transaction to unload.");
        this.printer.print("");
      }
    }

    // Check if execution has (just now) stopped.
    if (this.session.view(trace.finished) && !alreadyFinished) {
      this.printer.print("");
      //check if transaction failed
      if (!this.session.view(evm.transaction.status)) {
        this.printer.print("Transaction halted with a RUNTIME ERROR.");
        this.printer.print("");