from winreg import *
from contextlib import suppress
import itertools

def subkeys(path, hkey=HKEY_CLASSES_ROOT, flags=0):
    with suppress(WindowsError), OpenKey(hkey, path, 0, KEY_READ|flags) as k:
        for i in itertools.count():
            yield EnumKey(k, i)

def subvalues(path, hkey=HKEY_CLASSES_ROOT, flags=0):
    with suppress(WindowsError), OpenKey(hkey, path, 0, KEY_READ|flags) as k:
        for i in itertools.count():
            yield EnumValue(k, i)

for entry in subkeys(""):
    if "shell" not in list(subkeys(entry)):
        continue

    with suppress(WindowsError):
        key = OpenKey(HKEY_CLASSES_ROOT, f"{entry}\\shell\\open\\command")
        command = EnumValue(key, 0)[1]
        protocolEnabled = "URL Protocol" in (x[0] for x in subvalues(entry))
        if protocolEnabled:
            print(f"{entry:38} : {command}")