input: Write a function to modify the given Python program so that it prints 'Happy Holidays' 10 times. If the provided program is empty or invalid, return an empty string.
  assert print_happy_holidays("for i in range(10):\n    print('Hello World')")=="for i in range(10):\n    print('Happy Holidays')"
  assert print_happy_holidays("for i in range(5):\n    print('Hello')")=="for i in range(10):\n    print('Happy Holidays')"
  assert print_happy_holidays("")==""
  assert print_happy_holidays("print('Invalid')")==""
output: def print_happy_holidays(program):
      if not program or "print" not in program:
          return ""
      return "for i in range(10):\n    print('Happy Holidays')"