Python 类型错误：'；非类型'；对象不可订阅

我有一个python程序，它会产生一个错误：

def update_ranges(phonemelist) :
    """ updating the rows and columns of the list of input phonemes"""
    # make a copy of the list as we're going to modify it (optional)
    phonlist = phonemelist[:]
    # we don't need the row titles, they just complicate things
    rowtitles, phonlist = zip(*phonlist)
    rows = len(phonlist)
    columns = range(len(phonlist[0]))

    # for each row except the last
    for i in xrange(rows - 1):
        # update it by going down all the rows below it
        for k in xrange(i+1, rows):
            # for both columns
            for j in columns:
                update(phonlist, i, j, k, j)

    # put the row titles back in (optional)
    phonlist = zip(rowtitles, phonlist)
    return phonlist

def update(phonlist, curr_row, curr_col, next_row, next_col) :
    """ applying co-articulation rules for comparing the ranges """
    curr_low, curr_high = phonlist[curr_row][curr_col]
    next_low, next_high = phonlist[next_row][next_col]

    # Rule 1: when one of the ranges is (-1,-1)
    # replace the current range if it's (-1, -1) as its empty
    if (curr_low, curr_high) == (-1, -1) :
        phonlist[curr_row][curr_col] = next_low, next_high
        return
    # do nothing if the next range is (-1,-1)
    if (next_low, next_high) == (-1, -1) :
        return

    # Rule 2: when ranges don't overlap
    # replace the lowest value of current range when the next range is lower than the  current range   
    elif curr_low > next_high :
        phonlist[curr_row][curr_col] = curr_low, curr_low
        return 
    # replace the highest values of current range when the next range is higher than the current range
    elif next_low > curr_high :
        phonlist[curr_row][curr_col] = curr_high, curr_high 
        return 

    # Rule 3: when ranges completely overlap
    elif curr_low <= next_low and next_high <= curr_high or curr_low >= next_low and   next_high >= curr_high :
        # replace the values of the next range when the next range completely lies in the current range
        if curr_high - curr_low > next_high - next_low : 
            phonlist[curr_row][curr_col] = next_low, next_high
            return
        # replace the values of the current range when the current range completely lies in the next range
        else :
            phonlist[curr_row][curr_col] = curr_low, curr_high
            return

    # Rule 4: when the ranges partially overlap
    else :
        # replace the values that is common to both ranges when next range is further ahead of the current
        if curr_low < next_low and curr_high < next_high :
            phonlist[curr_row][curr_col] = next_low, curr_high
            return
        # replace the values that is common to both ranges when current range is further ahead of the next
        else :
            phonlist[curr_row][curr_col] = curr_low, next_high
            return 

---

错误的含义是什么？如何修复它？

这部分代码没有问题。也就是说

phonlist

或

不是

列表

（或订阅类型），而是

无

。查找创建列表的位置

编辑：

curr_low, curr_high = phonlist[curr_row][curr_col]
next_low, next_high = phonlist[next_row][next_col]

---

由于错误在第二行，我认为

phonlist[next_row]

是

None

这是Python在尝试从

None

值（Python的

null

等效值）访问下标（索引）值时返回的错误：

>a=None
>>>a[0]
回溯（最近一次呼叫最后一次）：
文件“”，第1行，在
TypeError:“非类型”对象不可下标

我的意思是，我首先在一个单独的文件中编写了这么多内容，并使用用户给定的输入。这是我研究项目的代码。当我把这个部分加入到我正在处理的大代码中，它从一个大列表中的文件中获取输入，然后它会显示这个错误。谢谢。我已经编辑了问题并添加了调用此函数的部分。是因为在phonlist[next_row][next_col]中没有传递值吗？与所有的比较一样，使用了phonlist[curr_row][curr_col]。很抱歉，有很多变量、函数和嵌套循环，很难弄清楚发生了什么。

phonlist[next_row]

curr_low, curr_high = phonlist[curr_row][curr_col]
next_low, next_high = phonlist[next_row][next_col]

>>> a = None
>>> a[0]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'NoneType' object is not subscriptable