Some context has been lost in the diff, I think. This `get` is not within any class, but at the module level and not overriding anything, in the spirit of this function not actually depending on any class.

If top level functions are not your jam, I would probably make a new class like this (which is good anyhow but I'm just keeping the changes incremental if the issue is not that important)

```python
class CouchDBKitApplication():
  """
  An application that automatically instantiates the appropriate model class
  based on the doc_type contained in the CouchDB document corresponding
  to an id.
  """

  def __init__(self, doc_type_classes):
     self.doc_type_classes = doc_type_classes

  def get(self, doc_id):
      # as above, using self.doc_type_classes
```