Make the port_number variable explicitly integer.
Make the port_number variable explicitly integer.

In Python3, write to port gave error message as
type(port_number) is a float, where the write() function
expected an integer. With this fix, commands such as
'board.digital[Pin11].write(1)' work without error, and show
a LED switched on if connected on the board...

tino/pyFirmata,jochasinga/pyFirmata,JoseU/pyFirmata