def METHOD_NAME(self, token_string, token_type_hint):
    """Get the token from database/storage by the given token string.
    Developers should implement this method::
        def query_token(self, token_string, token_type_hint):
            if token_type_hint == 'access_token':
                tok = Token.query_by_access_token(token_string)
            elif token_type_hint == 'refresh_token':
                tok = Token.query_by_refresh_token(token_string)
            else:
                tok = Token.query_by_access_token(token_string)
                if not tok:
                    tok = Token.query_by_refresh_token(token_string)
            return tok
    """
    raise NotImplementedError()