Return stat() info for *filename*. If *use_cache_only* is *False*,
    we will try to fetch the file if it is not cached.

def stat(filename, use_cache_only=False):
    """Return stat() info for *filename*. If *use_cache_only* is *False*,
    we will try to fetch the file if it is not cached."""
    filename = pyc2py(filename)
    if filename not in file_cache:
        if not use_cache_only: cache_file(filename)
        if filename not in file_cache:
            return None
        pass
    return file_cache[filename].stat