If we're willing to get our hands dirty, there is another way to create a monkey-patched version of `HTTPResponse` without copying and pasting the code. Basically we can define our subclass of `HTTPResponse`, and have our `begin` use the original `begin` function, but with a substituted scope. Say what?

Here is an example:

```python
import types

original = _HTTPResponse.begin

class HTTPResponse(_HTTPResponse):
    begin = types.FunctionType(original.func_code, dict(original.func_globals, HTTPMessage=HTTPMessage), original.func_name, original.func_defaults, original.func_closure)
```

So now instances of our class will resolve `HTTPMessage` to our version, but reuse the actual implementation of `begin` without any need to copy and paste code, or having to maintain that code.