diff --git a/tangostationcontrol/tangostationcontrol/toolkit/udp_simulator.py b/tangostationcontrol/tangostationcontrol/toolkit/udp_simulator.py
index 26488aaf7aca9df7dd875c22209c238956aa578c..98dc268056154be1a09850b452548b20746fed56 100644
--- a/tangostationcontrol/tangostationcontrol/toolkit/udp_simulator.py
+++ b/tangostationcontrol/tangostationcontrol/toolkit/udp_simulator.py
@@ -4,22 +4,28 @@
 import socket
 import time
 
-i = 1
-
 UDP_IP = "127.0.0.1"
 UDP_PORT = 5001
-MESSAGE = "{}".format(i)
 
-print(f"UDP target IP: {UDP_IP}")
-print(f"UDP target port: {UDP_PORT}")
 
-sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)  # create UDP socket
+def main():
+    message = "{}".format(i)
+    i = 1
+
+    print(f"UDP target IP: {UDP_IP}")
+    print(f"UDP target port: {UDP_PORT}")
+
+    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)  # create UDP socket
 
-if __name__ == "__main__":
     while True:
-        sock.sendto(bytes(MESSAGE, "utf-8"), (UDP_IP, UDP_PORT))
+        sock.sendto(bytes(message, "utf-8"), (UDP_IP, UDP_PORT))
         i += 1
-        MESSAGE = "{}".format(i)
+        message = "{}".format(i)
 
-        # sleep for an arbitrary amount of time. Currently 0.2 settings for visual testing.
+        # sleep for an arbitrary amount of time. Currently 0.2 settings for
+        # visual testing.
         time.sleep(0.2)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/tangostationcontrol/tox.ini b/tangostationcontrol/tox.ini
index a4c0c05490651f34cc0d5989c5680f80cfb9ea02..fef359345625278d65db1e360ae188756f857b4b 100644
--- a/tangostationcontrol/tox.ini
+++ b/tangostationcontrol/tox.ini
@@ -106,6 +106,7 @@ commands = {envpython} -m build
 envdir = {toxworkdir}/docs
 deps =
     -r{toxinidir}/../docker-compose/lofar-device-base/lofar-requirements.txt
+    -r{toxinidir}/requirements.txt
     -r{toxinidir}/docs/docs-requirements.txt
 commands =
     sphinx-build --version