def METHOD_NAME(
    self,
    since: float,
    selector: Callable[[pathlib.Path], bool],
) -> List[pathlib.Path]:
    """
    list_files returns Tensorboard-relevant file names located in the base_path directory
    and all sub-directories that have been modified since a certain time.
    If many files have been created, the syscall to stat on each of them can be quite
    expensive, taking on the order of 1ms for every 100 files. Each file gets stat'd every call
    to this function, which can be a bottleneck late in training or in local training when many
    files exist but few or none need to be re-synced.
    """
    if not self.base_path.exists():
        return []
    return [
        file
        for file in self.base_path.rglob("*")
        if file.stat().st_mtime > since and file.is_file() and selector(file)
    ]