Python PyInstaller: Cannot import win32serviceutil

Question

I created service.py. This is minimum working example:

import win32serviceutil


if __name__ == '__main__':
   pass

In a CMD console I run this:

pyinstaller.exe --onefile --hidden-import win32timezone service.py

However when I run service.exe, I get:

Traceback (most recent call last):
  File "service.py", line 2, in <module>
  File "PyInstaller\loader\pyimod03_importers.py", line 495, in exec_module
  File "win32serviceutil.py", line 9, in <module>
ImportError: DLL load failed: The specified procedure could not be found.
[20268] Failed to execute script 'service' due to unhandled exception!