请问这个报错怎么解决？

[wf52]

import time
from pyb import UART

# Always pass UART 3 for the UART number for your OpenMV Cam.
# The second argument is the UART baud rate. For a more advanced UART control
# example see the BLE-Shield driver.
uart = UART(3, 115200, timeout_char=1000)
while(True):
    print(uart.read())

[kidswong999]

https://singtown.com/learn/50240/

按照视频操作。