fix docs docker + docs type annotation

Author: rmorshea

docs/Dockerfile

@@ -1,4 +1,4 @@
-FROM python:3.8
+FROM python:3.9
 
 WORKDIR /app/
 
@@ -29,9 +29,9 @@ RUN pip install -e .[all]
 
 # Build the Docs
 # --------------
-ADD docs/main.py ./docs/
+ADD docs/app.py ./docs/
+ADD docs/examples.py ./docs/
 ADD docs/source ./docs/source
-ADD examples ./examples
 
 RUN pip install -r requirements/build-docs.txt
 RUN sphinx-build -b html docs/source docs/build

docs/source/_exts/widget_example.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import re
 from pathlib import Path
 from typing import Any