input: Write a python function to check if a number is a prime number.
  assert CheckPrime(2).is_prime() == True
  assert CheckPrime(3).is_prime() == True
  assert CheckPrime(4).is_prime() == False
  assert CheckPrime(17).is_prime() == True
  assert CheckPrime(20).is_prime() == False
output: class CheckPrime:
      def __init__(self, number):
          self.number = number
  
      def is_prime(self):
          if self.number <= 1:
              return False
          if self.number <= 3:
              return True
          if self.number % 2 == 0 or self.number % 3 == 0:
              return False
          i = 5
          while i * i <= self.number:
              if self.number % i == 0 or self.number % (i + 2) == 0:
                  return False
              i += 6
          return True