Is there any builtin operation in NumPy that returns the length of each string in an array?

I don't think any of the [NumPy string operations](https://docs.scipy.org/doc/numpy-1.12.0/reference/routines.char.html) does that, is this correct?

I can do it with a `for` loop, but maybe there's something more efficient?

```
import numpy as np
arr = np.array(['Hello', 'foo', 'and', 'whatsoever'], dtype='S256')

sizes = []
for i in arr:
    sizes.append(len(i))

print(sizes)
[5, 3, 3, 10]

```