How can I load an image with its alpha channel with skimage?

I am using an Anaconda distribution of Python with stuff like numpy, scipy, and scikit-image.

When I call:

from skimage import io
img = io.imread('myimage.png')

It ignores my alpha channel and returns the image as an array with shape (W, H, 3) instead of (W, H, 4). How can I get the alpha channel of the image?

from How can I load an image with its alpha channel with skimage?