Proposed fix:

1. Only import the utilities functions that we describe.
2. Describe all utility functions that are actually imported.

To do 1. you would need to specify the functions we import in the line

from .util.dtypes import *

To do 2. you would need to look at the file skimage.util.dtypes at the line

__all__ = [ ... ]

and give a short description of the functions that are imported.

Python lesson: the list __all__ describes the functions that are imported when you use from XXXX import *