Proplem in the final lab

I have done the final lab coding in week 4 and I passed all the tests.
but when i subit the lab for the final score , i fail with 0% ?
this always appears
NameError: name ‘UNQ_C1’ is not defined
i don’t know how to solve this error
this full message appeared once
Cell #18. Can’t compile the student’s code. Error: NameError(“name ‘UNQ_C1’ is not defined”)
Traceback (most recent call last):
File “/home/www/app/grading/”, line 112, in handle_solution_errors
yield {}
File “/home/www/app/grading/”, line 393, in _grade
context =
File “/home/www/app/grading/submission/”, line 195, in run
return list(self._code_items.values())[cell_num - 1].run()
File “/home/www/app/grading/submission/”, line 54, in run
return import_module(self.import_statement, items)
File “/usr/local/lib/python3.7/importlib/”, line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File “”, line 1006, in _gcd_import
File “”, line 983, in _find_and_load
File “”, line 967, in _find_and_load_unlocked
File “”, line 677, in _load_unlocked
File “”, line 728, in exec_module
File “”, line 219, in _call_with_frames_removed
File “/tmp/student_solution_cells/”, line 20, in
NameError: name ‘UNQ_C1’ is not defined

i solved the problem thanks

For those who find this thread later:
You have to be sure you don’t accidentally delete the comment that contains the grader’s key value. Every graded portion of the assignment has a key of the form “UNQ_C?”. It’s a comment in the first line of the graded cells.