Calling a clientsdie function when using an entity.

[Insomnia Array]

I've been wondering, what is a best way to call a function on clientside when using an certain entity. Say, I've got that function:

[lua]ENT:ClientFunction ()
print("derp")
end[/lua]

And I need it called on that specific entity when you press use on it. What would be the best way of doing so?

[King Flawless]

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