'Copy the cover to the file like object ``dest``. Returns False
if no cover exists or dest is the same file as the current cover.
dest can also be a path in which case the cover is
copied to it if and only if the path is different from the current path (taking
case sensitivity into account).'

@read_api
def copy_cover_to(self, book_id, dest, use_hardlink=False, report_file_size=None):

    try:
        path = self._field_for(u'path', book_id).replace(u'/', os.sep)
    except AttributeError:
        return False
    return self.backend.copy_cover_to(path, dest, use_hardlink=use_hardlink, report_file_size=report_file_size)
