How to use the aliyun-python-sdk-core-v3.aliyunsdkcore.auth.composer.roa_signature_composer function in aliyun-python-sdk-core-v3

"""
        Generate signed header
        :param region_id: String
        :param ak: String
        :param secret: String
        :return: Dict
        """
        sign_params = self._get_sign_params()
        if self.get_content() is not None:
            md5_str = md5_tool.get_md5_base64_str(self.get_content())
            self.add_header('Content-MD5', md5_str)
        if 'RegionId' not in sign_params.keys():
            sign_params['RegionId'] = region_id
            self.add_header('x-acs-region-id', region_id)

        signed_headers = roa_signer.get_signature_headers(
            sign_params,
            ak,
            secret,
            self.get_accept_format(),
            self.get_headers(),
            self.get_uri_pattern(),
            self.get_path_params(),
            self.get_method())
        return signed_headers

def get_url(self, region_id, ak=None, secret=None):
        """
        Compose request url without domain
        :param region_id: String
        :return: String
        """
        sign_params = self.get_query_params()
        # if region_id not in sign_params.keys():
        #     sign_params['RegionId'] = region_id
        url = roa_signer.get_url(
            self.get_uri_pattern(),
            sign_params,
            self.get_path_params())
        return url

def __build_query_string(uri, queries):
    sorted_map = sorted(list(queries.items()), key=lambda queries: queries[0])
    if len(sorted_map) > 0:
        uri += "?"
        for (k, v) in sorted_map:
            uri += k
            if v is not None:
                uri += "="
                uri += v
            uri += roa_signature_composer.QUERY_SEPARATOR
    if uri.find(roa_signature_composer.QUERY_SEPARATOR) >= 0:
        uri = uri[0:(len(uri) - 1)]
    return uri

def __build_query_string(uri, queries):
    sorted_map = sorted(list(queries.items()), key=lambda queries: queries[0])
    if len(sorted_map) > 0:
        uri += "?"
        for (k, v) in sorted_map:
            uri += k
            if v is not None:
                uri += "="
                uri += v
            uri += roa_signature_composer.QUERY_SEPARATOR
    if uri.find(roa_signature_composer.QUERY_SEPARATOR) >= 0:
        uri = uri[0:(len(uri) - 1)]
    return uri