Can you use random events to change tags.

I was wondering if you would be able to say have a random number and then if the number was say, 1 then add tag happy.
I tried using the following code but it came up with this error: "Error: <<if>>: assignment operator found within <<if>> clause (perhaps you meant to use an equality operator: ==, ===, eq, is), invalid: $random="1" add tag happy"
<<print random(1,2)>>
<<if $random="1" add tag happy>><</if>>