""" Set The Priority of a Windows Process.  Priority is a value between 0-5 where
    2 is normal priority.  Default sets the priority of the current
    python process but can take any valid process ID. """
import win32api, win32process, win32con
priorityclasses = [win32process.IDLE_PRIORITY_CLASS, win32process.
    BELOW_NORMAL_PRIORITY_CLASS, win32process.NORMAL_PRIORITY_CLASS,
    win32process.ABOVE_NORMAL_PRIORITY_CLASS, win32process.
    HIGH_PRIORITY_CLASS, win32process.REALTIME_PRIORITY_CLASS]
if pid == None:
    pid = win32api.GetCurrentProcessId()
handle = win32api.OpenProcess(win32con.PROCESS_ALL_ACCESS, True, pid)
win32process.SetPriorityClass(handle, priorityclasses[priority])
Nicing a running python process?