input: Write a python function to return the nth prime number.
  assert nth_prime_number(1) == 2
  assert nth_prime_number(2) == 3
  assert nth_prime_number(5) == 11
  assert nth_prime_number(10) == 29
output: def nth_prime_number(n):
      def is_prime(num):
          if num < 2:
              return False
          for i in range(2, int(num**0.5) + 1):
              if num % i == 0:
                  return False
          return True
  
      count = 0
      current_number = 1
      while count < n:
          current_number += 1
          if is_prime(current_number):
              count += 1
  
      return current_number