Merge pull request #328 from PrefectHQ/refactor-ai_fn-prompt-outside-…

…of-run

move out prompt generation from _run to own _method

src/marvin/ai_functions/base.py

@@ -152,7 +152,7 @@ def __call__(self, *args, **kwargs):
 
         return output
 
-    async def _run(self, *args, **kwargs):
+    async def __prompt__(self, *args, **kwargs):
         # Get function signature
         sig = inspect.signature(self.fn)
 
@@ -178,7 +178,10 @@ async def _run(self, *args, **kwargs):
             input_binds=bound_args.arguments,
             yield_value=yield_value,
         )
+        return message
 
+    async def _run(self, *args, **kwargs):
+        message = await self.__prompt__(*args, **kwargs)
         bot = self.get_bot()
         response = await bot.say(message)
         return response.parsed_content