Answer
$y = 2+\frac{1}{4}~sec~(\frac{1}{2}x-\pi)$
We can see the graph below.
Work Step by Step
$y = 2+\frac{1}{4}~sec~(\frac{1}{2}x-\pi)$
When $x = -\pi$, then $y = 2+\frac{1}{4}~sec~\frac{-3\pi}{2}$ (which is undefined)
When $x = 0$, then $y = 2+\frac{1}{4}~sec~(-\pi) = \frac{7}{4}$
When $x = \pi$, then $y = 2+\frac{1}{4}~sec~(-\frac{\pi}{2})$ (which is undefined)
When $x = 2\pi$, then $y = 2+\frac{1}{4}~sec~0 = \frac{9}{4}$
When $x = 3\pi$, then $y = 2+\frac{1}{4}~sec~\frac{\pi}{2}$ (which is undefined)
We can see the graph below.