ValueError -1 ValueError 0 UART 1 UART 2 UART 3 UART 4 ValueError 5 UART 6 ValueError 7 UART XA UART XB UART YA UART YB ValueError Z UART(1, baudrate=9600, bits=8, parity=None, stop=1, flow=0, timeout=1000, timeout_char=3, read_buf_len=64) UART(1, baudrate=2400, bits=8, parity=None, stop=1, flow=0, timeout=1000, timeout_char=7, read_buf_len=64) 0 3 4 None 1 4 None None