'The time of the last scan data.
This may be the time of the scan or the modification time of the
buffer content at the last scan.  Typically this is set via the
\'mtime\' optional argument to scan().
This returns None if this file hasn\'t been scanned.'

@property
def scan_time(self):

    self.acquire_lock()
    try:
        if (self._scan_time_cache is None):
            try:
                self._load_buf_data_once()
            except NotFoundInDatabase:
                pass
        return self._scan_time_cache
    finally:
        self.release_lock()
