ROS机器人turtlesim走直线的简单python示例代码不需要注释

以下是ROS机器人turtlesim走直线的简单python示例代码，无需注释：

#!/usr/bin/env python

import rospy
from geometry_msgs.msg import Twist

def move():
    # 初始化ROS节点
    rospy.init_node('move_turtle', anonymous=True)

    # 创建一个发布者，用于发布速度控制消息
    velocity_publisher = rospy.Publisher('/turtle1/cmd_vel', Twist, queue_size=10)

    # 创建一个Twist消息，用于控制机器人运动
    vel_msg = Twist()

    # 设置机器人直线运动的速度
    vel_msg.linear.x = .5
    vel_msg.linear.y = 
    vel_msg.linear.z = 

    # 设置机器人旋转运动的速度
    vel_msg.angular.x = 
    vel_msg.angular.y = 
    vel_msg.angular.z = 

    # 计算机器人运动的时间
    t = rospy.Time.now().to_sec()
    distance = 2
    speed = .5
    time = distance / speed

    # 控制机器人运动
    while not rospy.is_shutdown() and (rospy.Time.now().to_sec() - t) < time:
        velocity_publisher.publish(vel_msg)

    # 停止机器人运动
    vel_msg.linear.x = 
    velocity_publisher.publish(vel_msg)

if __name__ == '__main__':
    try:
        move()
    except rospy.ROSInterruptException:
        pass