Week2 exercise 8

I am stuck on week 2’s exercise 8.
I am getting:
AssertionError Traceback (most recent call last)
----> 1 model_test(model)

~/work/release/W2A2/public_tests.py in model_test(target)
113 assert type(d[‘costs’]) == list, f"Wrong type for d[‘costs’]. {type(d[‘costs’])} != list"
→ 114 assert len(d[‘costs’]) == 1, f"Wrong length for d[‘costs’]. {len(d[‘costs’])} != 1"
115 assert np.allclose(d[‘costs’], expected_output[‘costs’]), f"Wrong values for pred. {d[‘costs’]} != {expected_output[‘costs’]}"

AssertionError: Wrong length for d[‘costs’]. 20 != 1

Is there any part of the code I currently have that would help you instruct me further?

Welcome to the Specialization @minreie! This thread addresses the same issue. Note: The questions from the learner are in Spanish. I use Google translate, but the context should be clear from @paulinpaloalto’s response.