def change_karma(user_id, karma):
user_karma = UtilDB.get_value_by_user_id("karma", user_id)
if user_karma is not None:
user_karma = user_karma[1]
else:
user_karma = 0
UtilDB.set_value_by_user_id("karma", user_id, "karma", (user_karma + karma))
return user_karma + karma
