input: Write a python function to find the roots of a quadratic equation using the provided class.
  assert QuadraticEquation(1, -3, 2).get_roots() == ((1+0j), (2+0j))
  assert QuadraticEquation(1, 2, 1).get_roots() == ((-1+0j), (-1+0j))
  assert QuadraticEquation(1, 0, -4).get_roots() == ((-2+0j), (2+0j))
output: import cmath
  
  class QuadraticEquation:
      def __init__(self, a, b, c):
          self.a = a
          self.b = b
          self.c = c
  
      def get_roots(self):
          d = cmath.sqrt(self.b**2 - 4*self.a*self.c)
          root1 = (-self.b + d) / (2 * self.a)
          root2 = (-self.b - d) / (2 * self.a)
          return (root1, root2)