Brake booster line?

Hey all,

I want to seafoam my engine, and I have read the entire thread, but I honestly don't know where this "brake booster line" is that I'm supposed to stick down in the seafoam bottle.

I'm assuming it's in this area somewhere, because that reservoir is the brake master cylinder (right?)

Can anyone point out to me in this picture (or a different one) where I might find the line to disconnect and stick in the seafoam bottle on an 08 i4 tibby?

Thanks, beautifuls.