input: Write a function to determine if a given number is prime or composite. If the number is prime, return 'Prime'; otherwise, return 'Composite'.
  assert is_prime(2) == 'Prime'
  assert is_prime(15) == 'Composite'
  assert is_prime(1) == 'Prime'
  assert is_prime(29) == 'Prime'
  assert is_prime(100) == 'Composite'
output: def is_prime(n):
      if n <= 1:
          return 'Composite'
      for i in range(2, int(n**0.5) + 1):
          if n % i == 0:
              return 'Composite'
      return 'Prime'