Minor tweak to doc on HTTP 400s
Add a sentence clarifying that setting DEFAULT_VALIDATION_STATUS
requires sublcassing the parser for your framework.
resolves
@@ -440,6 +440,7 @@ Returning HTTP 400 Responses
If you'd prefer validation errors to return status code ``400`` instead
of ``422``, you can override ``DEFAULT_VALIDATION_STATUS`` on a :class:`Parser <webargs.core.Parser>`.
+Sublcass the parser for your framework to do so. For example, using Falcon:
.. code-block:: python
