DouKaku?

from __future__ import with_statement
from contextlib import contextmanager
import ctypes

GMEM_DDESHARE = 0x2000
GMEM_MOVEABLE = 0x0002
CF_TEXT = 1

user32 = ctypes.windll.user32
kernel32 = ctypes.windll.kernel32

@contextmanager
def _GlobalLock(h):
    p = kernel32.GlobalLock(h)
    if not p:
        raise WindowsError("GlobalLock() failed")
    try:
        yield p
    finally:
        kernel32.GlobalUnlock(h)

@contextmanager
def _Clipboard():
    if not user32.OpenClipboard(None):
        raise WindowsError("OpenClipboard() failed")
    try:
        yield
    finally:
        user32.CloseClipboard()

def set(s):
    s = s.encode("mbcs")
    # memory block
    h = kernel32.GlobalAlloc(GMEM_DDESHARE | GMEM_MOVEABLE, len(s) + 1)
    if not h:
        raise WindowsError("GlobalAlloc() failed")
    try:
        with _GlobalLock(h) as p:
            p = (ctypes.c_char * (len(s) + 1)).from_address(p)
            for i, c in enumerate(s + "\0"):
                p[i] = c
        # clipboard
        with _Clipboard():
            user32.EmptyClipboard()
            user32.SetClipboardData(CF_TEXT, h)
    except:
        kernel32.GlobalFree(h)
        raise

def get():
    with _Clipboard():
        h = user32.GetClipboardData(CF_TEXT)
        if h:
            with _GlobalLock(h) as p:
                return ctypes.c_char_p(p).value.decode("mbcs")

def clear():
    with _Clipboard():
        user32.EmptyClipboard()