There's some sort of bogus character at the end of that source. Try deleting the last line and adding it back.
I can't figure out exactly what's there, yet ...
edit — I think it's a zero-width space, Unicode 200B. Seems pretty weird and I can't be sure of course that it's not a Stackoverflow artifact, but when I copy/paste that last function including the complete last line into the Chrome console, I get your error.
A notorious source of such characters are websites like jsfiddle. I'm not saying that there's anything wrong with them — it's just a side-effect of something, maybe the use of content-editable input widgets.
If you suspect you've got a case of this ailment, and you're on MacOS or Linux/Unix, the od command line tool can show you (albeit in a fairly ugly way) the numeric values in the characters of the source code file. Some IDEs and editors can show "funny" characters as well. Note that such characters aren't always a problem. It's perfectly OK (in most reasonable programming languages, anyway) for there to be embedded Unicode characters in string constants, for example. The problems start happening when the language parser encounters the characters when it doesn't expect them.
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