--- render-pngs.py	(original)
+++ render-pngs.py	(refactored)
@@ -82,7 +82,7 @@
 	def isFloat(self, stringVal):
 		try:
 			return (float(stringVal), True)[1]
-		except (ValueError, TypeError), e:
+		except (ValueError, TypeError) as e:
 			return False
 
 	def parseCoordinates(self, val):
@@ -236,7 +236,7 @@
 	xmlParser.setContentHandler(svgLayerHandler)
 	try:
 		xmlParser.parse(svgFilename)
-	except SAXParseException, e:
+	except SAXParseException as e:
 		fatalError("Error parsing SVG file '%s': line %d,col %d: %s.  If you're seeing this within inkscape, it probably indicates a bug that should be reported." % (svgfile, e.getLineNumber(), e.getColumnNumber(), e.getMessage()))
 
 	# verify that the svg file actually contained some rectangles.