input: Write a function to check if the given string contains the word "Hello". If it contains "Hello", return True; otherwise, return False. If the given string is empty, return False.
  assert check_hello("Hello World")==True
  assert check_hello("hello world")==False
  assert check_hello("Hi there, Hello!")==True
  assert check_hello("This is a test")==False
  assert check_hello("")==False
output: def check_hello(s):
      if not s:
          return False
      return "Hello" in s