@classmethod
def _check_maintenance_alarm(cls, check, machine, counter):
    """Check, if it is time to maintaine machine."""
    header = ''
    if not check.isnull().any() and int(counter) <= 0:
        header = ('\n\x1b[91mПодошло ТО для:\x1b[0m ' + machine +
            ' дата последнего ТО: ' + check.values[0])
    return header
