如何使用SMTP-lib通过gmail发送电子邮件，而不将其作为密件抄送？

import smtplib
from email.mime.text import MIMEText

# 连接到gmail的SMTP服务器
smtp_server = 'smtp.gmail.com'
smtp_port = 587
smtp_connection = smtplib.SMTP(smtp_server, smtp_port)
smtp_connection.starttls()

# 进行身份验证
gmail_username = 'your_email@gmail.com'
gmail_password = 'your_password'
smtp_connection.login(gmail_username, gmail_password)

# 创建电子邮件
sender = 'your_email@gmail.com'
recipient = 'recipient_email@example.com'
subject = 'Test Email'
body = 'This is a test email.'
message = MIMEText(body)
message['From'] = sender
message['To'] = recipient
message['Subject'] = subject

# 发送电子邮件
smtp_connection.sendmail(sender, recipient, message.as_string())

# 关闭连接
smtp_connection.quit()