input: Write a python function to identify prime numbers from a list.
  assert identify_primes([2, 4, 7, 11, 13]) == [2, 7, 11, 13]
  assert identify_primes([1, 3, 5, 6, 8]) == [3, 5]
  assert identify_primes([10, 15, 17, 19, 21]) == [17, 19]
output: def identify_primes(nums):
      def is_prime(n):
          if n <= 1:
              return False
          for i in range(2, int(n**0.5) + 1):
              if n % i == 0:
                  return False
          return True
      
      return [num for num in nums if is_prime(num)]