'Represent for the Tall Out number,
if show_link is True then it will generate a link to the pdf'

@staticmethod
def inv_send_ref_represent(value, show_link=True):

    if value:
        if show_link:
            db = current.db
            table = db.inv_send
            row = db((table.send_ref == value)).select(table.id, limitby=(0, 1)).first()
            if row:
                return A(value, _href=URL(c='inv', f='send', args=[row.id, 'form']))
            else:
                return value
        else:
            return value
    else:
        return current.messages['NONE']
