No such file or directory: '/c/Users/lotuslwt/.vim/bundle/clang_complete/plugin/libclang.py'

[lotuslwt]

I'm runing vim in git-bash (git-for-windows), my related facilities show below:
. python version: 3.83 (64bit)
. llvm(clang) version: 6.01
vim show supporting python & python3 (+python/dyn, +python3/dyn)

My vimrc files has following setting:
let &pythonthreedll = 'D:\Program Files\Python\Python38\python38.dll'
let g:clang_library_path='D:\Program Files\LLVM\lib'

Run in vim :python3 print("hello, world")，get 'hello, world', perfect!
but when I open a C language source file, it prompt something wrong:

"test.c" [dos] 8L, 113C
Error detected while processing function 34_ClangCompleteInit[146]..34_initClangCompletePython:
line 14:
Traceback (most recent call last):
File "", line 1, in
FileNotFoundError: [Errno 2] No such file or directory: '/c/Users/lotuslwt/.vim/bundle/clang_complete/plugin/libclang.py'
line 26:
Snippets engine dummy not found

Actually, the libclang.py exist in that folder
$ ls /c/Users/lotuslwt/.vim/bundle/clang_complete/plugin/
clang clang_complete.vim kinds.py libclang.py snippets

I google a long time but get nothing, so what shall I do?