Fix logic for preparing model with no default example

Signed-off-by: Mattt Zmuda <mattt@replicate.com>

Author: mattt

replicate/model.py

@@ -143,7 +143,8 @@ def prepare_model(self, attrs: Union[Model, Dict]) -> Model:
             attrs.id = f"{attrs.owner}/{attrs.name}"
         elif isinstance(attrs, dict):
             attrs["id"] = f"{attrs['owner']}/{attrs['name']}"
-            attrs.get("default_example", {}).pop("version", None)
+            if "default_example" in attrs and "version" in attrs["default_example"]:
+                attrs["default_example"].pop("version", None)
 
         model = super().prepare_model(attrs)