input: Write a python function to create a Rectangle class with methods for area and perimeter.
  assert Rectangle(3, 4).area() == 12
  assert Rectangle(3, 4).perimeter() == 14
  assert Rectangle(5, 5).area() == 25
  assert Rectangle(5, 5).perimeter() == 20
output: def Rectangle:
      def __init__(self, width, height):
          self.width = width
          self.height = height
      
      def area(self):
          return self.width * self.height
      
      def perimeter(self):
          return 2 * (self.width + self.height)