Сортировка с применением анонимной функции lamda

import os
 
path = './files/'
 
def readfile(path: str):
    files_list = os.listdir(path) 
    text = {} #Определяем пустой словарь
    for some_file in files_list:
        if some_file.rfind('.txt', -4): 
          with open(os.path.join(path, some_file), 'r', encoding='utf-8') as file:
            text[some_file] = file.readlines()
 
    with open('final_file.txt', 'w', encoding='utf-8') as file:
      
        for file_name, rows in sorted(text.items, key=lambda x: x[1]):  
            file.write(final_file.txt + '\n')
            file.write(str(len(rows)) + '\n')
            if '\n' not in rows[-1]:
                rows[-1] += '\n'
            file.write(''.join(rows))
 
 
readfile(path)

for file_name, rows in sorted(text.items, key=lambda x: x[1]):

for file_name, rows in sorted(text.items(), key=lambda x: -len(x[1])):

d = {}
for i in range(1, 3):
    name = f'{i}.txt'
    with open(name, 'r', encoding='utf-8') as f:
        d[name] = [x for x in f.read().splitlines() if x]
 
with open('final_file.txt', 'w', encoding='utf-8') as file:
    for k, v in sorted(d.items(), key=lambda x: -len([x[1]])):
        file.write(k + '\n')
        file.write(str(len(v)) + '\n')
        file.write('\n'.join(v))
        file.write('\n')

for file_name, rows in sorted(text.items(), key=lambda x: len(x[-1])):