运行时出现下面的错误:

Traceback (most recent call last):
  File "D:/Projects/project_name/tools/train.py", line 178, in <module>
    main()
  File "D:/Projects/project_name/tools/train.py", line 167, in main
    train_detector(
  File "D:\Projects\project_name\mmdet\apis\train.py", line 147, in train_detector
    runner.resume(cfg.resume_from)
  File "D:\Anaconda3\envs\hzmd\lib\site-packages\mmcv\runner\base_runner.py", line 346, in resume
    config = mmcv.Config.fromstring(
  File "D:\Anaconda3\envs\hzmd\lib\site-packages\mmcv\utils\config.py", line 279, in fromstring
    cfg = Config.fromfile(temp_file.name)
  File "D:\Anaconda3\envs\hzmd\lib\site-packages\mmcv\utils\config.py", line 251, in fromfile
    cfg_dict, cfg_text = Config._file2dict(filename,
  File "D:\Anaconda3\envs\hzmd\lib\site-packages\mmcv\utils\config.py", line 137, in _file2dict
    Config._substitute_predefined_vars(filename,
  File "D:\Anaconda3\envs\hzmd\lib\site-packages\mmcv\utils\config.py", line 112, in _substitute_predefined_vars
    with open(filename, 'r') as f:
PermissionError: [Errno 13] Permission denied: 'C:\\Users\\Admin\\AppData\\Local\\Temp\\tmp06sdogpt.py'

这是因为mmcv\utils\config.py的_file2dict()函数想在C盘创建临时文件，但是PyTorch没有在C盘创建文件的权限，因此造成了PermissionError.解决的办法是在D盘创建一个Temp文件夹,让_file2dict()在D盘创建临时文件，就不会有PermissionError了.因此对_file2dict(filename, use_predefined_variables=True)这个函数进行了修改:

    @staticmethod
    def _file2dict(filename, use_predefined_variables=True):
        filename = osp.abspath(osp.expanduser(filename))
        filenames = filename.split('\\')
        if filenames[0] == 'C:':
            filename = 'D:\\Temp\\' +filenames[-1]
            f = open(filename, 'w')
            f.close()
        check_file_exist(filename)
        fileExtname = osp.splitext(filename)[1]
        if fileExtname not in ['.py', '.json', '.yaml', '.yml']:
            raise IOError('Only py/yml/yaml/json type are supported now!')

        with tempfile.TemporaryDirectory() as temp_config_dir:
            temp_config_dir = 'D:\\Temp\\' + temp_config_dir.split('\\')[-1]
            os.makedirs(temp_config_dir)
            temp_config_file = tempfile.NamedTemporaryFile(
                dir=temp_config_dir, suffix=fileExtname)
            if platform.system() == 'Windows':
                temp_config_file.close()
            temp_config_name = osp.basename(temp_config_file.name)
            # Substitute predefined variables
            if use_predefined_variables:
                Config._substitute_predefined_vars(filename,
                                                   temp_config_file.name)
            else:
                shutil.copyfile(filename, temp_config_file.name)

先判断是否在C盘创建临时文件,如果是,则在D:\Temp下创建相同名字的临时文件夹和文件,这样就不会有PermissionError了.