# Buggy code
def _unprotect_file(path):
    if System.is_symlink(path) or System.is_hardlink(path):
        logger.debug("Unprotecting '{}'".format(path))
        tmp = os.path.join(os.path.dirname(path), "." + str(uuid.uuid4()))

        # The operations order is important here - if some application
        # would access the file during the process of copyfile then it
        # would get only the part of file. So, at first, the file should be
        # copied with the temporary name, and then original file should be
        # replaced by new.
        copyfile(
            path,
            tmp,
            name="Unprotecting '{}'".format(os.path.relpath(path)),
        )
        remove(path)
        os.rename(tmp, path)

    else:
        logger.debug(
            "Skipping copying for '{}', since it is not "
            "a symlink or a hardlink.".format(path)
        )

    os.chmod(path, os.stat(path).st_mode | stat.S_IWRITE)


# Traceback (ValueError)
ERROR: failed to pull data from the cloud - path is on mount 'F:', start on mount 'C:'
Traceback (most recent call last):
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\command\data_sync.py", line 46, in
do_run recursive=self.args.recursive,
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\repo\pull.py", line 24, in pull
recursive=recursive,
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\repo\fetch.py", line 27, in fetch
used, jobs, remote=remote, show_checksums=show_checksums
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\data_cloud.py", line 144, in pull
show_checksums=show_checksums,
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\remote\local\__init__.py", line 493, in pull
download=True,
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\remote\local\__init__.py", line 459, in _process
download=download,
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\remote\local\__init__.py", line 358, in status
local_exists = self.cache_exists(md5s)
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\remote\local\__init__.py", line 232, in cache_exists
return list(filter(lambda md5: not self.changed_cache_file(md5), md5s))
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\remote\local\__init__.py", line 232, in <lambda>
return list(filter(lambda md5: not self.changed_cache_file(md5), md5s))
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\remote\base.py", line 518, in changed_cache_file
actual = self.get_checksum(cache_info)
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\remote\base.py", line 275, in get_checksum
checksum = self.get_file_checksum(path_info)
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\remote\local\__init__.py", line 208, in get_file_checksum
return file_md5(path_info.path)[0]
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\site-packages\dvc\utils\__init__.py", line 48, in file_md5                      logger.info(msg.format(os.path.relpath(fname)))
File "c:\users\srg\appdata\local\continuum\anaconda3\envs\tf-keras\lib\ntpath.py", line 584, in relpath
path_drive, start_drive))                                                                                                                        ValueError: path is on mount 'F:', start on mount 'C:'

# Fixed code
def _unprotect_file(path):
    if System.is_symlink(path) or System.is_hardlink(path):
        logger.debug("Unprotecting '{}'".format(path))
        tmp = os.path.join(os.path.dirname(path), "." + str(uuid.uuid4()))

        # The operations order is important here - if some application
        # would access the file during the process of copyfile then it
        # would get only the part of file. So, at first, the file should be
        # copied with the temporary name, and then original file should be
        # replaced by new.
        copyfile(path, tmp, name="Unprotecting '{}'".format(relpath(path)))
        remove(path)
        os.rename(tmp, path)

    else:
        logger.debug(
            "Skipping copying for '{}', since it is not "
            "a symlink or a hardlink.".format(path)
        )

    os.chmod(path, os.stat(path).st_mode | stat.S_IWRITE)