I wrote my answer like below but can’t figure out why it is not correct. Can someone help please? thanks a lot

```
y_hat=x*m+b
total_cost=np.sum((y_hat-y)**2)/(2*m)
```

The error was

```
<class 'numpy.float64'>
Cost at initial w: 377446.185
---------------------------------------------------------------------------
AssertionError Traceback (most recent call last)
<ipython-input-95-335d76763737> in <module>
9 # Public tests
10 from public_tests import *
---> 11 compute_cost_test(compute_cost)
~/work/public_tests.py in compute_cost_test(target)
9 initial_b = 3.0
10 cost = target(x, y, initial_w, initial_b)
---> 11 assert cost == 0, f"Case 1: Cost must be 0 for a perfect prediction but got {cost}"
12
13 # Case 2
AssertionError: Case 1: Cost must be 0 for a perfect prediction but got 60.0
```