当我运行代码时，它在“genre_id = cur.fetchone（）[0]"行中显示type error，我不知道发生了什么。它对我来说很有意义，但我不知道哪里出错了。它开始做列表，但停在一个部分。我尝试改变顺序，但没有意义，我看到的解决方案基本相同，但名称不同，...它工作，但不明白为什么我的不工作

import xml.etree.ElementTree as ET
import sqlite3

conn = sqlite3.connect('trackdb.sqlite')
cur = conn.cursor()

# Make some fresh tables using executescript()
cur.executescript('''

DROP TABLE IF EXISTS Artist;
DROP TABLE IF EXISTS Genre;
DROP TABLE IF EXISTS Album;
DROP TABLE IF EXISTS Track;
CREATE TABLE Artist (
    id  INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT UNIQUE,
    name    TEXT UNIQUE
);
CREATE TABLE Genre (
    id  INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT UNIQUE,
    name    TEXT UNIQUE
);
CREATE TABLE Album (
    id  INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT UNIQUE,
    artist_id  INTEGER,
    title   TEXT UNIQUE
);
CREATE TABLE Track (
    id  INTEGER NOT NULL PRIMARY KEY
        AUTOINCREMENT UNIQUE,
    title TEXT  UNIQUE,
    album_id  INTEGER,
    genre_id  INTEGER,
    len INTEGER, rating INTEGER, count INTEGER
);
''')

fname = input('Enter file name: ')
if ( len(fname) < 1 ) : fname = 'Library.xml'

# <key>Track ID</key><integer>369</integer>
# <key>Name</key><string>Another One Bites The Dust</string>
# <key>Artist</key><string>Queen</string>
def lookup(d, key):
    found = False
    for child in d:
        if found : return child.text
        if child.tag == 'key' and child.text == key :
            found = True
    return None

stuff = ET.parse(fname)
all = stuff.findall('dict/dict/dict')
print('Dict count:', len(all))
for entry in all:
    if ( lookup(entry, 'Track ID') is None ) : continue

    name = lookup(entry, 'Name')
    artist = lookup(entry, 'Artist')
    genre = lookup(entry, 'Genre')
    album = lookup(entry, 'Album')

    if name is None or artist is None or album is None :
        continue

    print(name, artist, album, genre) #cambiar aber

    cur.execute('''INSERT OR IGNORE INTO Artist (name)
        VALUES ( ? )''', ( artist, ) )
    cur.execute('SELECT id FROM Artist WHERE name = ? ', (artist, ))
    artist_id = cur.fetchone()[0]

    cur.execute('''INSERT OR IGNORE INTO Genre (name)
        VALUES ( ? )''', ( genre, ) )
    cur.execute('SELECT id FROM Genre WHERE name = ? ', (genre, ))
    genre_id = cur.fetchone()[0]

    cur.execute('''INSERT OR IGNORE INTO Album (title, artist_id)
        VALUES ( ?, ? )''', ( album, artist_id ) )
    cur.execute('SELECT id FROM Album WHERE title = ? ', (album, ))
    album_id = cur.fetchone()[0]

    cur.execute('''INSERT OR REPLACE INTO Track
        (title, album_id, genre_id)
        VALUES ( ?, ?, ?)''',
        (name, album_id, genre_id) )

    conn.commit()