add .py to the list of jupytext-readable extensions

Author: parmentelat

ipypublish/convert/main.py

@@ -132,7 +132,7 @@ def _default_pre_conversion_funcs(self):
             # this is deprecated in newer versions
             from jupytext import readf as read  # noqa: F401
 
-        return {".Rmd": read, ".md": read}
+        return {".Rmd": read, ".md": read, ".py": read}
 
     @validate("pre_conversion_funcs")
     def _validate_pre_conversion_funcs(self, proposal):