Question: 
Write a function to find the focus of a parabola.


Model's Code:
def parabola_focus(a, b, c):
    p = 1 / (4 * a)
    h = -b / (2 * a)
    k = c - (b ** 2) / (4 * a)
    return (h, k + p)



Sample Correct Code:
def parabola_focus(a, b, c): 
  focus= (((-b / (2 * a)),(((4 * a * c) - (b * b) + 1) / (4 * a))))
  return focus


Asserts:
assert parabola_focus(5,3,2)==(-0.3, 1.6)
assert parabola_focus(9,8,4)==(-0.4444444444444444, 2.25)
assert parabola_focus(2,4,6)==(-1.0, 4.125)


Tests:
Test 1 of 3: PASS
Test 2 of 3: PASS
Test 3 of 3: PASS

Test 185 of 974: 135/185 (72.97297297297297%): success