human
Solve the following python programming problem given the following code:
@ classmethod 
def _TryAcquire(cls, client, resource_type, resource_id, callback, resource_data = None, detect_abandonment = False, owner_id = None, attempts = 0, test_hook = None) : 
    'Helper method that makes "MAX_UPDATE_ATTEMPTS" to acquire the
    lock. If multiple agents are trying to acquire the lock, then one
    might be updating the lock in order to acquire it while another
    is querying the lock in order to see if it can be acquired. These
    race conditions are resolved by detecting changes and retrying.

    The "test_hook" function is called just before an attempt is made
    to update the Lock row in the database. This makes testing various
    race conditions much easier.
    ' 
    def _OnUpdate(lock, status) : 
        'If lock was acquired and abandonment needs to be detected,
      then starts renewal timer.
      ' 
        if ((status != Lock.FAILED_TO_ACQUIRE_LOCK) and detect_abandonment) : 
            lock._Renew (client) 
callback (lock, status) 
def _OnException(type, value, tb) : 
        'Starts over unless too many acquire attempts have been made.' 
        logging.warning (('race condition caused update of "%s:%s" lock to fail (will retry): %s' % (resource_type, resource_id, value))) 
        if (attempts >= Lock.MAX_UPDATE_ATTEMPTS) : 
            logging.error ('too many failures attempting to update lock.
aborting', exc_info = (type, value, tb)) 
            callback (None, Lock.FAILED_TO_ACQUIRE_LOCK) 
else : 
            Lock._TryAcquire (client, resource_type, resource_id, callback, resource_data = resource_data, detect_abandonment = detect_abandonment, attempts = (attempts + 1), test_hook = test_hook) 
def _DoUpdate(update_func) : 
        'Calls the test hook just before a row is updated in the database.
      Tests can simulate updates made by another agent at this critical
      juncture.
      ' 
        if (test_hook is not None) : 
            test_hook (update_func) 
else : 
            update_func () 
def _OnQuery(lock) : 
        'Creates a new lock, takes...

    
    

    Fix the buggy line: Lock.Query (client, lock_id, None, test_hook, must_exist = False)
assistant
#Here is Python code to fix the buggy line: Lock.

Lock.Query (client, lock_id, None, def _OnQuery(, must_exist = False)