input: Write a python function to find the roots of a quadratic equation.
  assert quadratic_equation_roots(1, -3, 2) == (2.0, 1.0)
  assert quadratic_equation_roots(1, 2, 1) == (-1.0, -1.0)
  assert quadratic_equation_roots(1, 0, -4) == (2.0, -2.0)
  assert quadratic_equation_roots(1, 0, 4) == "This equation has no real roots!"
output: def quadratic_equation_roots(a, b, c):
      import math
      discriminant = b**2 - 4*a*c
      if discriminant > 0:
          root1 = (-b + math.sqrt(discriminant)) / (2*a)
          root2 = (-b - math.sqrt(discriminant)) / (2*a)
          return (root1, root2)
      elif discriminant == 0:
          root = -b / (2*a)
          return (root, root)
      else:
          return "This equation has no real roots!"