Getting an assertion error in exercise 5

```
AssertionError Traceback (most recent call last)
<ipython-input-22-7cd89fb9dcd2> in <module>
14 print ("cost = " + str(cost))
15
---> 16 propagate_test(propagate)
~/work/release/W2A2/public_tests.py in propagate_test(target)
41 assert np.allclose(grads['dw'], expected_dw), f"Wrong values for grads['dw']. {grads['dw']} != {expected_dw}"
42 assert np.allclose(grads['db'], expected_db), f"Wrong values for grads['db']. {grads['db']} != {expected_db}"
---> 43 assert np.allclose(cost, expected_cost), f"Wrong values for cost. {cost} != {expected_cost}"
44 print('\033[92mAll tests passed!')
45
AssertionError: Wrong values for cost. 12.519827193591217 != 2.0424567983978403
```

The code to calculate cost is below

```
A = sigmoid(np.dot(w.T,X)+b)
cost = (-1/m)*(np.sum(Y*np.log(A).T + (1-Y)*np.log(1-A).T))
```