Use Oxford comma properly in getex
@@ -843,7 +843,7 @@ class Commands:
opset = set([ex, px, exat, pxat])
if len(opset) > 2 or len(opset) > 1 and persist:
- raise DataError("``ex``, ``px``, ``exat``, ``pxat``",
+ raise DataError("``ex``, ``px``, ``exat``, ``pxat``, "
"and ``persist`` are mutually exclusive.")
pieces = []
