Removing text from a variable

Removing text from a variable

Hi,

I'm trying to remove text from a variable in Zoho Flow with a Custom Function.
So the variable name is setVariable_2
A variable could be "Dennis van Gulik (ValueIT B.V.)", it is from a dropdown field from Zoho Forms.
And I want the output to be "Dennis van Gulik"

Has anyone a simple solution for this, or knows the code. I can't find it for the life of me.

Kind regards Dennis van Gulik