Anti-parallel wires executing SHM!

Two long parallel and horizontal wires, each of radius R, carrying current 2A & 3A, respectively are arranged in a vertical plane one above the other. The lower wire is clamped fixed while the upper one is free to move up and down in vertical plane and maintains an equilibrium separation of D . The length of each wire L>> D .

The upper wire is pressed slightly and released so as to execute simple harmonic motion in vertical plane. What is the observed time period(in secs.) of such a motion?

$\text{ Assume: D= 0.2 cm, L= 20m}$ , g= 10 m/ $s^{2}$ , $\mu_{0}$ = 4π x $10^{-7}$ H/m