Updates the hunt object by applying the update function.

def UpdateHuntObject(self,
                       hunt_id,
                       duration=None,
                       client_rate=None,
                       client_limit=None,
                       hunt_state=None,
                       hunt_state_comment=None,
                       start_time=None,
                       num_clients_at_start_time=None):
    """Updates the hunt object by applying the update function."""
    _ValidateHuntId(hunt_id)
    precondition.AssertOptionalType(duration, rdfvalue.Duration)
    precondition.AssertOptionalType(client_rate, (float, int))
    precondition.AssertOptionalType(client_limit, int)
    if hunt_state is not None:
      _ValidateEnumType(hunt_state, rdf_hunt_objects.Hunt.HuntState)
    precondition.AssertOptionalType(hunt_state_comment, str)
    precondition.AssertOptionalType(start_time, rdfvalue.RDFDatetime)
    precondition.AssertOptionalType(num_clients_at_start_time, int)

    return self.delegate.UpdateHuntObject(
        hunt_id,
        duration=duration,
        client_rate=client_rate,
        client_limit=client_limit,
        hunt_state=hunt_state,
        hunt_state_comment=hunt_state_comment,
        start_time=start_time,
        num_clients_at_start_time=num_clients_at_start_time)