'Copy the format ``fmt`` to the file like object ``dest``. If the
specified format does not exist, raises :class:`NoSuchFormat` error.
dest can also be a path, in which case the format is copied to it, iff
the path is different from the current path (taking case sensitivity
into account).'

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

    fmt = (fmt or u'').upper()
    try:
        name = self.fields[u'formats'].format_fname(book_id, fmt)
        path = self._field_for(u'path', book_id).replace(u'/', os.sep)
    except (KeyError, AttributeError):
        raise NoSuchFormat((u'Record    %d    has    no    %s    file' % (book_id, fmt)))
    return self.backend.copy_format_to(book_id, fmt, name, path, dest, use_hardlink=use_hardlink, report_file_size=report_file_size)
