input: Write a function to iterate over a list of numbers and print only the even numbers. If the list is empty, print "No numbers to process". If the list contains non-number elements, print "Invalid input".
  assert print_even_numbers([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])==None
  assert print_even_numbers([])
  assert print_even_numbers([2, 4, 6, 8, 10])==None
  assert print_even_numbers([1, 3, 5, 7, 9])==None
  assert print_even_numbers([1, 'a', 3])==None
output: def print_even_numbers(numbers):
      if not numbers:
          print("No numbers to process")
          return
      for num in numbers:
          if not isinstance(num, (int, float)):
              print("Invalid input")
              return
      for num in numbers:
          if num % 2 == 0:
              print(num)