Fixed two variable references.

No functional effect at this point.

gitstats

 	
 	##
 	# Save cacheable data
-	def saveCache(self, filename):
+	def saveCache(self, cachefile):
 		print 'Saving cache...'
 		f = open(cachefile, 'w')
 		#pickle.dump(self.cache, f)
 				self.tags[tag] = { 'stamp': stamp, 'hash' : hash, 'date' : datetime.datetime.fromtimestamp(stamp).strftime('%Y-%m-%d'), 'commits': 0, 'authors': {} }
 
 		# collect info on tags, starting from latest
-		tags_sorted_by_date_desc = map(lambda el : el[1], reversed(sorted(map(lambda el : (el[1]['date'], el[0]), data.tags.items()))))
+		tags_sorted_by_date_desc = map(lambda el : el[1], reversed(sorted(map(lambda el : (el[1]['date'], el[0]), self.tags.items()))))
 		prev = None
 		for tag in reversed(tags_sorted_by_date_desc):
 			cmd = 'git shortlog -s "%s"' % tag