GetDescriptorById.
        [Preview API]
        :param str id:
        :param bool is_master_id:
        :rtype: :class:`<str> <azure.devops.v5_0.identity.models.str>`

def get_descriptor_by_id(self, id, is_master_id=None):
        """GetDescriptorById.
        [Preview API]
        :param str id:
        :param bool is_master_id:
        :rtype: :class:`<str> <azure.devops.v5_0.identity.models.str>`
        """
        route_values = {}
        if id is not None:
            route_values['id'] = self._serialize.url('id', id, 'str')
        query_parameters = {}
        if is_master_id is not None:
            query_parameters['isMasterId'] = self._serialize.query('is_master_id', is_master_id, 'bool')
        response = self._send(http_method='GET',
                              location_id='a230389a-94f2-496c-839f-c929787496dd',
                              version='5.0-preview.1',
                              route_values=route_values,
                              query_parameters=query_parameters)
        return self._deserialize('str', response)