def connect(self): 
        try:
            self.connection = pymongo.Connection(self.host, self.port)
            self.db = self.connection[self.name]
        except AutoReconnect:
            raise DatabaseException("It's not possible connect to the database")
def remove(root, key):
    left, right = split(root, key)
    return merge(left, split(right, key + 1)[1])