The problem here is in separating your function calls. I came up with a solution that split your text on commas but then I saw that certain function calls contain commas and that wouldn't work.

Try separating each function call with something other than a comma, like a special character. Then you can split that string on that character and grep out the duplicates.

Better yet, forgo putting the calls in a string and put them in an array and then grep that.