You will have to create a structure called `Message`, which contains:
- elements:
-`content`: `String`
-`user`: `String`
- associated functions:
-`new`: which initializes the structure.
-`send_ms`: which only has its implementation type (**self**) as argument. It should return `None` if the content of the message is either **empty** or contains the word **stupid**. It should return the content of the message otherwise.
You will also need to create a **function** named `check_ms` which accepts a reference to a `Message`, and returns a tuple. This function will invoke the `send_ms` function.
- If `send_ms` returns `None`, then your function should return `false` and `"ERROR: illegal"`.
- Else, your function should return `true` and the contents of the message sent.