读取python文件中的水平行

因此，我试图想出一个suduko检查代码。其中所需的数据存储在外部文件中。我正在检查数字是否水平匹配。到目前为止，我有以下几点

filename=input("Enter filename:-")

with open(filename) as f:  #opening files
    content = f.readlines()  #obtaining each lines  

for line in lines:             #check each line
    numbers=line.split()  #split each line    # split(example 135246 into 1,3,5,2,4,6 )
    newnumber=letter.sort()   #arrange to 1,2,3,4,5,6
    if newnumber=[1,2,3,4,5,6]:
         print("valid")
    else:
         print("not valid")

我想知道这是否适用于检查水平数字

filename=input("Enter filename:-")

with open(filename) as f:  #opening files
    for line in f:
        numbers = [int(i) for i in line.strip()]
        numbers.sort()
        if numbers == list(range(1,7)):
            print("valid")
        else:
            print("invalid")