small error correction

* +x to main.py
+ added catch for a None response as some xeps have addition tags some do not have

classes/xep.py

@@ -75,17 +75,16 @@ class XEPRequest:
 		# if requested number is member of acceptedxeps continue
 		if str(self.reqxep) in self.acceptedxeps:
 			searchstring = ".//*[@accepted='true']/[number='%s']" % self.reqxep
+			query = None
 
 			for item in self.xeplist.findall(searchstring):
 				# if the opt_arg references is member of xeptag return only that tag
 				if self.opt_arg in xep_tags:
 					query = item.find(self.opt_arg)
-					result.append("%s : %s" % (query.tag, query.text))
 
 				# if the opt_arg references is member of last-revision_tags return only that tag
 				elif self.opt_arg in last_revision_tags:
 					query = item.find("last-revision").find(self.opt_arg)
-					result.append("%s : %s" % (query.tag, query.text))
 
 				# in any other case return the general answer
 				else:
@@ -93,6 +92,12 @@ class XEPRequest:
 					for tag in result_opts:
 						result.append(item.find(tag).text)
 
+				# append opt_arg results to the result list
+				if query is not None:
+					result.append("%s : %s" % (query.tag, query.text))
+				else:
+					result.append("%s does not have a %s tag." % (self.reqxep, self.opt_arg))
+
 		# if the requested number is no member of acceptedxeps and/or not accepted return error.
 		else:
 			result.append("XEP-%s : is not available." % self.reqxep)