micropython/examples/hwapi/hwconfig_pyboard.py

from machine import Pin, Signal

# Red LED on pin LED_RED also known as A13
LED = Signal("LED_RED", Pin.OUT)

# Green LED on pin LED_GREEN also known as A14
LED2 = Signal("LED_GREEN", Pin.OUT)

# Yellow LED on pin LED_YELLOW also known as A15
LED3 = Signal("LED_YELLOW", Pin.OUT)

# Blue LED on pin LED_BLUE also known as B4
LED4 = Signal("LED_BLUE", Pin.OUT)