Fix Python 3 'urllib' error message

[cederlys]

When using Python 3.9.7, simply starting pyShell() produces this error
message:

AttributeError: module 'urllib' has no attribute 'request'

Fix, by importing urllib.request before attempting to use
urllib.request.urlopen.

This small demo program triggers the error:

#!/usr/bin/env python3

import sys
import time

from pyShelly import pyShelly

shelly = pyShelly()

while True:
    try:
        time.sleep(60)
    except KeyboardInterrupt:
        print("Bye!")
        sys.exit(0)

[e-v-k]

Would be great if this could be merged to master.

[kornpow]

Ran into this issue as well. Running Python 3.11. Seems strange that a library which seems to be well maintained has show-stopping issue when trying to run the demo application in the README? Maybe HA has an older Python3 bundled in and this hasnt been prioritized?

[ramack]

It would be cool, if we can have this merged and released!