sphinx fix

conf.py

@@ -15,6 +15,12 @@ extensions = [
     'sphinx.ext.viewcode',
 ]
 
+
+# Uncomment the below if you use native CircuitPython modules such as
+# digitalio, micropython and busio. List the modules you use. Without it, the
+# autodoc module docs will fail to generate with a warning.
+autodoc_mock_imports = ["micropython", "adafruit_bus_device"]
+
 intersphinx_mapping = {'python': ('https://docs.python.org/3.4', None),'BusDevice': ('https://circuitpython.readthedocs.io/projects/bus_device/en/latest/', None),'CircuitPython': ('https://circuitpython.readthedocs.io/en/latest/', None)}
 
 # Add any paths that contain templates here, relative to this directory.