在使用App Store Connect API的Python代码中，需要提供有效的认证凭据才能成功访问API。通常，这些凭据会包括您的开发人员帐户的凭据和您的API密钥。如果您在运行代码时遇到了“Authentication credentials are missing or invalid”的错误消息，则说明您的凭据未正确配置或已过期。要解决此问题，请使用正确的凭据重新配置您的API访问代码，例如：

import jwt
import requests

# Replace with your own values
issuer_id = 'YOUR_ISSUER_ID_HERE'
key_id = 'YOUR_KEY_ID_HERE'
private_key_file = 'PATH_TO_YOUR_PRIVATE_KEY.p8'

# Load your private key
with open(private_key_file, 'r') as f:
    private_key = f.read()

# Generate the JWT
headers = {'alg': 'ES256', 'kid': key_id}
claims = {'iss': issuer_id, 'exp': time.time()+60*10, 'aud': 'appstoreconnect-v1'}
jwt_token = jwt.encode(claims, private_key, algorithm='ES256', headers=headers)

# Make the API request
headers = {'Authorization': 'Bearer ' + jwt_token.decode('utf-8')}
url = 'https://api.appstoreconnect.apple.com/v1/apps'
response = requests.get(url, headers=headers)

# Process the response
if response.status_code == 200:
    data = response.json()
    print('Number of apps:', len(data['data']))
else:
    print('API request failed with code', response.status_code)
    print(response.json())

在此代码示例中，我们使用Python JWT库生成API请求所需的JWT令牌，并使用此令牌设置API请求的Authorization标头。请注意，您将需要替换示例代码中的一些值，例如您的发行人ID、密钥ID和私钥文件路径。正确配置后，您应该能够成功访问App Store Connect API并获得API响应数据。