Some People have been having trouble unlocking the Magnetic Lift Shortcut on Paper Street. Unfortunately this is available once per play throw (New game Plus works). This guide will show you how to unlock the lift. If your here its likely because you missed it, if you plan on playing New Game Plus this will help you unlock it for next time.
How to Unlock
Complete the "Delicatessen" side quest up to the point in which you kill Penelope. after you get Penelope's Key open the door and talk to Jennifer.
When she ask you for a reward take the reward. The reward is "Jenny's Keycard" which can be confused with "Penelope's Key" (the person you just killed).
Jenny's Keycard allows you to use the Magnetic Lift.