"""P9-2 I2C Bus Scanner"""
from machine import Pin, I2C

i2c = I2C(1, scl = Pin(27), sda = Pin(26), freq = 400_000)

dev_list = []
for dev_addr in range(8, 0x7F):    # exclude special addresses
    try:
        i2c.writevto(dev_addr, ())
    except OSError:  # if OSError encountered
        pass
    else:            # if no OSError
        dev_list.append(dev_addr)  # add the device address to the list
    finally:         # regardless of errors
        pass

print(dev_list)