```
here is some code
```

That's using the *fenced-code-blocks* extra.

Here is an empty one (just to check):

```
```

Here is one at the end of the file:

```
    is indentation maintained?
```

Here's one in a list, with another one following (see #580):

* List 1
  ```
  code 1

  code 2
  ```

```
code 3
```