Does not work on Windows OS

```
import os
import sys
from ctypes import *

lib = cdll.LoadLibrary(r'myrustlib.dll')
val='tesTTanotheRRtesTTtest'
lib.count_doubles(val)
```

errors out:
```

    func = self._FuncPtr((name_or_ordinal, self))
AttributeError: function 'count_doubles' not found

```

