Request): A callable used to make
            HTTP requests.
        token_uri (str): The OAuth 2.0 authorizations server's token endpoint
            URI.
        body (Mapping[str, str]): The parameters to send in the request body.
        access_token (Optional(str)): The access token needed to make the request.
        use_json (Optional(bool)): Use urlencoded format or json format for the
            content type. The default value is False.
        can_retry (bool): Enable or disable request retry behavior.
        headers (Optional[Mapping[str, str]]): The headers for the request.
        kwargs: Additional arguments passed on to the request method. The
            kwargs will be passed to `requests.request` method, see:
            https://docs.python-requests.org/en/latest/api/#requests.request.
            For example, you can use `cert=("cert_pem_path", "key_pem_path")`
            to set up client side SSL certificate, and use
            `verify="ca_bundle_path"` to set up the CA certificates for sever
            side SSL certificate verification.

    Returns:
        Mapping[str, str]: The JSON-decoded response data.

    Raises:
        google.auth.exceptions.RefreshError: If the token endpoint returned
            an error.
    )