Hi there,

I am writing my `sigmoid`

function for the final lab on course 1 and getting this error:

```
AssertionError Traceback (most recent call last)
<ipython-input-116-11ebc8ea1ba1> in <module>
3 # UNIT TESTS
4 from public_tests import *
----> 5 sigmoid_test(sigmoid)
~/work/public_tests.py in sigmoid_test(target)
3
4 def sigmoid_test(target):
----> 5 assert np.isclose(target(3.0), 0.9525741268224334), "Failed for scalar input"
6 assert np.allclose(target(np.array([2.5, 0])), [0.92414182, 0.5]), "Failed for 1D array"
7 assert np.allclose(target(np.array([[2.5, -2.5], [0, 1]])),
AssertionError: Failed for scalar input
```

It appears the failure is expecting the value `3`

for the `sigmoid`

function, however, I thought the sigmoid produces values 0 > g(z) > 1. Or is the input of the function `3`

and the expected output the `0.9525741268224334`

?