input: Write a function to print only the even numbers from a given list of numbers using a for loop. If the list is empty, print "No numbers to print". If there are no even numbers in the list, print "No even numbers found".
  
  assert print_even_numbers([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])=="2\n4\n6\n8\n10\n"
  assert print_even_numbers([1, 3, 5, 7, 9])=="No even numbers found"
  assert print_even_numbers([])=="No numbers to print"
  assert print_even_numbers([2, 4, 6, 8, 10])=="2\n4\n6\n8\n10\n"
output: def print_even_numbers(numbers):
      if not numbers:
          print("No numbers to print")
          return
      found_even = False
      for num in numbers:
          if num % 2 == 0:
              print(num)
              found_even = True
      if not found_even:
          print("No even numbers found")