@@ -143,7 +143,7 @@ clean:
 venv:
 	$(PYTHON) -m venv $(VENVDIR)
 	$(VENVDIR)/bin/python3 -m pip install -U pip setuptools
-	$(VENVDIR)/bin/python3 -m pip install -U Sphinx==2.2.0 blurb python-docs-theme
+	$(VENVDIR)/bin/python3 -m pip install -U Sphinx==2.3.1 blurb python-docs-theme
 	@echo "The venv has been created in the $(VENVDIR) directory"
 
 dist:
 
@@ -0,0 +1 @@
+Pin Sphinx version to 2.3.1 in ``Doc/Makefile``.
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	+Pin Sphinx version to 2.3.1 in ``Doc/Makefile``.