'Return a list of all time zones known to the system.'

@staticmethod
def list():

    handle = winreg.ConnectRegistry(None, winreg.HKEY_LOCAL_MACHINE)
    tzkey = winreg.OpenKey(handle, TZKEYNAME)
    result = [winreg.EnumKey(tzkey, i) for i in range(winreg.QueryInfoKey(tzkey)[0])]
    tzkey.Close()
    handle.Close()
    return result
