def isip(item):
    item    = item.strip()
    items   = item.split('.')
    if len(items) != 4 or item == "0.0.0.0" or item == "255.255.255.255": return False
    else :
        for i in range(0,3):
            if not items[i].isdigit() or items[i] < "0" or items[i] > "255": return False
    return True