Quick sample to reproduce json escaping with pyhomematic. Please replace PASSWORD with a valid password of the CCU.

homematic-test.py

import time
import sys
import logging
from pyhomematic import HMConnection

logging.basicConfig(level=logging.DEBUG)

def systemcallback(src, *args):
    print(src)
    for arg in args:
        print(arg)

try:
    pyhomematic = HMConnection(systemcallback=systemcallback, autostart=True, remotes={"local":{"ip":"192.168.32.242", "port": 2001, "username":"Admin", "password": "PASSWORD"}})
except Exception:
    sys.exit(1)

sleepcounter = 0

def eventcallback(address, interface_id, key, value):
    print("CALLBACK: %s, %s, %s, %s" % (address, interface_id, key, value))

while not pyhomematic.devices and sleepcounter < 20:
    print("Waiting for devices")
    sleepcounter += 1
    time.sleep(1)
print(pyhomematic.devices)

print(pyhomematic.getAllSystemVariables("local"))


# Stop the server thread so Python can exit properly.
pyhomematic.stop()

sys.exit(0