key = 'HKEY_LOCAL_MACHINE\SOFTWARE\TightVNC\Server' ## Here give the registry Key path. STRING
Sub_Key= "UseVncAuthentication" ## Here give the sub Key of the registry. STRING
Field= "REG_DWORD" ##Here give the field of it (E.g) REG_DWORD or REG_SZ
value = 0 ##Mention the value


import os
import subprocess
import ctypes

class disable_file_system_redirection:
    _disable = ctypes.windll.kernel32.Wow64DisableWow64FsRedirection
    _revert = ctypes.windll.kernel32.Wow64RevertWow64FsRedirection
    def __enter__(self):
        self.old_value = ctypes.c_long()
        self.success = self._disable(ctypes.byref(self.old_value))
    def __exit__(self, type, value, traceback):
        if self.success:
            self._revert(self.old_value)
with disable_file_system_redirection():
	cmd = 'reg add "'+key+'" /v '+Sub_Key+' /t '+Field+'  /d {0} /f'.format(value)
	#print cmd
	obj = subprocess.Popen(cmd, shell=True, stdout = subprocess.PIPE, stderr = subprocess.PIPE)
	out, err = obj.communicate()
	if err:
		print(err)
	else:
		print("Require VNC Authentication Disabled.")