input: Write a python function to calculate the perimeter of a polygon using the Polygon class.
  assert Polygon([3, 4, 5]).perimeter() == 12
  assert Polygon([5, 5, 5, 5]).perimeter() == 20
  assert Polygon([1, 2, 3, 4, 5]).perimeter() == 15
output: class Polygon:
      def __init__(self, sides):
          self.sides = sides
  
      def perimeter(self):
          return sum(self.sides)