def minadj(lsttup):
    """
    Taka a list of tuple as its parameter, then return
    an adjacency which it is not visited/explored/black
    with minimum weight / cost.
    """
    templist = []
    for tup in lsttup:
        if tup[0].color == "white":
            templist.append(tup)
    templist.sort(key= lambda weigth: weigth[-1])
    choosenadj = templist[0]
    return choosenadj