当尝试从backpack.tf获取OAuth授权时，如何修复“错误：(401)未授权”？

https://backpack.tf/auth/authorize?client_id=YOUR_CLIENT_ID&redirect_uri=YOUR_REDIRECT_URI&response_type=code&scope=user

import requests

# 替换为你的客户端ID和密钥
client_id = 'your_client_id'
client_secret = 'your_client_secret'
redirect_uri = 'https://yourapp.com/callback'

# 获取授权码
auth_url = f'https://backpack.tf/auth/authorize?client_id={client_id}&redirect_uri={redirect_uri}&response_type=code&scope=user'
print(f'Please visit this URL to authorize the app: {auth_url}')

# 用户授权后，backpack.tf会重定向到你的redirect_uri，并附带一个授权码
authorization_code = input('Enter the authorization code: ')

# 使用授权码获取访问令牌
token_url = 'https://backpack.tf/auth/token'
data = {
    'client_id': client_id,
    'client_secret': client_secret,
    'code': authorization_code,
    'redirect_uri': redirect_uri,
    'grant_type': 'authorization_code'
}

response = requests.post(token_url, data=data)
if response.status_code == 200:
    token_info = response.json()
    access_token = token_info['access_token']
    print(f'Access Token: {access_token}')
else:
    print(f'Error: {response.status_code} - {response.text}')