python如何调用dll库

def CreateGUID():       

"""     

创建一个全局唯一标识符     

类似：E06093E2-699A-4BF2-A325-4F1EADB50E18     

NewVersion     

"""       

try:           

# dll path           

strDllPath = sys.path[0] + str(os.sep) + "createguid.dll"           

dll = CDLL(strDllPath)           

b = dll.newGUID()           

a = c_char_p(b)       

except Exception, error:           

print error           

return ""       

return a.value

from ctypes import *         

# 定义_PROCESS_INFORMATION结构体   

class _PROCESS_INFORMATION(Structure):       

_fields_ = [('hProcess', c_void_p),                   

('hThread', c_void_p),                   

('dwProcessId', c_ulong),                   

('dwThreadId', c_ulong)]        

# 定义_STARTUPINFO结构体   

class _STARTUPINFO(Structure):       

_fields_ = [('cb',c_ulong),                   

('lpReserved', c_char_p),                   

('lpDesktop', c_char_p),                   

('lpTitle', c_char_p),                   

('dwX', c_ulong),                   

('dwY', c_ulong),                   

('dwXSize', c_ulong),                   

('dwYSize', c_ulong),                   

('dwXCountChars', c_ulong),                   

('dwYCountChars', c_ulong),                   

('dwFillAttribute', c_ulong),                   

('dwFlags', c_ulong),                   

('wShowWindow', c_ushort),                   

('cbReserved2', c_ushort),                   

('lpReserved2', c_char_p),                   

('hStdInput', c_ulong),                   

('hStdOutput', c_ulong),                   

('hStdError', c_ulong)]        

NORMAL_PRIORITY_CLASS = 0x00000020 #定义NORMAL_PRIORITY_CLASS   

kernel32 = windll.LoadLibrary("kernel32.dll")  #加载kernel32.dll   

CreateProcess = kernel32.CreateProcessA   #获得CreateProcess函数地址   

ReadProcessMemory = kernel32.ReadProcessMemory #获得ReadProcessMemory函数地址   

WriteProcessMemory = kernel32.WriteProcessMemory #获得WriteProcessMemory函数地址   

TerminateProcess = kernel32.TerminateProcess         # 声明结构体   

ProcessInfo = _PROCESS_INFORMATION()   

StartupInfo = _STARTUPINFO()   

fileName = 'c:/windows/notepad.exe'       # 要进行修改的文件   

address = 0x0040103c        # 要修改的内存地址   

strbuf = c_char_p("_")        # 缓冲区地址   

bytesRead = c_ulong(0)       # 读入的字节数   

bufferSize =  len(strbuf.value)     # 缓冲区大小        

# 创建进程    

CreateProcess(fileName, 0, 0, 0, 0, NORMAL_PRIORITY_CLASS,0, 0, byref(StartupInfo), byref(ProcessInfo))