UDATE

using System;
using System.Runtime.InteropServices;

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct SYSTEMTIME
{
    public ushort wYear;
    public ushort wMonth;
    public ushort wDayOfWeek;
    public ushort wDay;
    public ushort wHour;
    public ushort wMinute;
    public ushort wSecond;
    public ushort wMilliseconds;
}

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct UDATE
{
    public SYSTEMTIME st;
    public ushort wDayOfYear;
}

Imports System.Runtime.InteropServices

<StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Unicode)>
Public Structure SYSTEMTIME
    Public wYear As UShort
    Public wMonth As UShort
    Public wDayOfWeek As UShort
    Public wDay As UShort
    Public wHour As UShort
    Public wMinute As UShort
    Public wSecond As UShort
    Public wMilliseconds As UShort
End Structure

<StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Unicode)>
Public Structure UDATE
    Public st As SYSTEMTIME
    Public wDayOfYear As UShort
End Structure

import ctypes
from ctypes import wintypes

class SYSTEMTIME(ctypes.Structure):
    _fields_ = [
        ("wYear", ctypes.c_ushort),
        ("wMonth", ctypes.c_ushort),
        ("wDayOfWeek", ctypes.c_ushort),
        ("wDay", ctypes.c_ushort),
        ("wHour", ctypes.c_ushort),
        ("wMinute", ctypes.c_ushort),
        ("wSecond", ctypes.c_ushort),
        ("wMilliseconds", ctypes.c_ushort),
    ]

class UDATE(ctypes.Structure):
    _fields_ = [
        ("st", SYSTEMTIME),
        ("wDayOfYear", ctypes.c_ushort),
    ]

#[repr(C)]
pub struct SYSTEMTIME {
    pub wYear: u16,
    pub wMonth: u16,
    pub wDayOfWeek: u16,
    pub wDay: u16,
    pub wHour: u16,
    pub wMinute: u16,
    pub wSecond: u16,
    pub wMilliseconds: u16,
}

#[repr(C)]
pub struct UDATE {
    pub st: SYSTEMTIME,
    pub wDayOfYear: u16,
}

import "golang.org/x/sys/windows"

type SYSTEMTIME struct {
	wYear uint16
	wMonth uint16
	wDayOfWeek uint16
	wDay uint16
	wHour uint16
	wMinute uint16
	wSecond uint16
	wMilliseconds uint16
}

type UDATE struct {
	st SYSTEMTIME
	wDayOfYear uint16
}

type
  SYSTEMTIME = record
    wYear: Word;
    wMonth: Word;
    wDayOfWeek: Word;
    wDay: Word;
    wHour: Word;
    wMinute: Word;
    wSecond: Word;
    wMilliseconds: Word;
  end;

  UDATE = record
    st: SYSTEMTIME;
    wDayOfYear: Word;
  end;

const SYSTEMTIME = extern struct {
    wYear: u16,
    wMonth: u16,
    wDayOfWeek: u16,
    wDay: u16,
    wHour: u16,
    wMinute: u16,
    wSecond: u16,
    wMilliseconds: u16,
};

const UDATE = extern struct {
    st: SYSTEMTIME,
    wDayOfYear: u16,
};

type
  SYSTEMTIME {.bycopy.} = object
    wYear: uint16
    wMonth: uint16
    wDayOfWeek: uint16
    wDay: uint16
    wHour: uint16
    wMinute: uint16
    wSecond: uint16
    wMilliseconds: uint16

  UDATE {.bycopy.} = object
    st: SYSTEMTIME
    wDayOfYear: uint16

struct SYSTEMTIME
{
    ushort wYear;
    ushort wMonth;
    ushort wDayOfWeek;
    ushort wDay;
    ushort wHour;
    ushort wMinute;
    ushort wSecond;
    ushort wMilliseconds;
}

struct UDATE
{
    SYSTEMTIME st;
    ushort wDayOfYear;
}