def __headers(self):
        """
        Get HTTP headers for a HTTP/HTTPS SOAP request.

        @return: A dictionary of header/values.
        @rtype: dict

        """
        action = self.method.soap.action
        if isinstance(action, unicode):
            action = action.encode("utf-8")
        result = {
            "Content-Type": "text/xml; charset=utf-8",
            "SOAPAction": action}
        result.update(**self.options.headers)
        log.debug("headers = %s", result)
        return result