Version bump

Author: Arjan Zijderveld

setup.py

@@ -43,7 +43,7 @@
     # For a discussion on single-sourcing the version across setup.py and the
     # project code, see
     # https://packaging.python.org/en/latest/single_source_version.html
-    version='0.9.0',  # Required
+    version='0.9.1',  # Required
 
     # This is a one-line description or tagline of what your project does. This
     # corresponds to the "Summary" metadata field: