input: Write a function to determine if the given string contains the word "Hello". If it does, return True, otherwise return False.
  def check_hello(s):
      return 'Hello' in s
  
  assert check_hello("Hello, world!")==True
  assert check_hello("Hi there!")==False
  assert check_hello("Say Hello to the world.")==True
  assert check_hello("")==False
  assert check_hello("HelloHello")==True
output: def check_hello(s):
      return 'Hello' in s