如何从google cloud (代号1)获取oauth2身份验证令牌，然后使用它向云自然语言API发出请求

from google.oauth2 import service_account
from google.auth.transport.requests import Request

# 定义您的凭据文件路径
credentials = service_account.Credentials.from_service_account_file(
    'path/to/your/credentials.json',
    scopes=['https://www.googleapis.com/auth/cloud-platform']
)

# 检查是否存在有效的令牌，如果没有则刷新
if credentials.expired:
    credentials.refresh(Request())

# 获取访问令牌
access_token = credentials.token

from googleapiclient.discovery import build

# 创建云自然语言API客户端
language_service = build('language', 'v1', credentials=credentials)

# 构建请求
request = language_service.documents().analyzeSentiment(
    body={
        'document': {
            'type': 'PLAIN_TEXT',
            'content': 'Hello, how are you?'
        }
    }
)

# 发送请求并获取响应
response = request.execute()

# 处理响应数据
sentiment = response['documentSentiment']['score']