psutil on Windows: How can resident set size (rss) be greater than virtual memory size (wms)?

Question

When I run this little Python code on Windows:

import psutil
print(psutil.Process().memory_info())

I get the following output:

pmem(rss=13578240L, vms=8323072L, num_page_faults=4293, peak_wset=13582336L, wset=13578240L, peak_paged_pool=119872L, pa
ged_pool=119696L, peak_nonpaged_pool=9624L, nonpaged_pool=9560L, pagefile=8323072L, peak_pagefile=8323072L, private=8323
072L)

which indicates that the resident set size (rss) is greater than the virtual memory size (vms). How's that possible? On Linux I get rss <= vms.