Hello All, 

 I have a question. I am attempting to do the Build an Instant Notification App project. I am trying to add some code in the Apex Class to get the SessionId as instructed in the Subscribe to Platform Event.

Here is the code:
 

@AuraEnabled public static String getSessionId() { return UserInfo.getSessionId(); }

In creating the method and trying to save it, I get the following error under the Developer Console:

unexpected token: 'String'

Can anyone please help as I don't understand why this error would come up. Thank you in advance.