Connecting to a Vehicle in a Multi Vehicle Link

Hi.
I am using RFD900x telemetry modules to connect multiple vehicles one by one.
I am using the the following commands.
To connect to telemetry:
mavproxy.exe --master=COM256,57600 --out=127.0.0.1:10000 --out=127.0.0.1:10010 --out=127.0.0.1:10020 --out=127.0.0.1:10030 --cmd="set shownoise false" --daemon
To connect and distribute vehicle one by one:
mavproxy.exe --master=udpin:127.0.0.1:10010 --target-system=10 --cmd="set shownoise false" --out=127.0.0.1:20010
mavproxy.exe --master=udpin:127.0.0.1:10020 --target-system=20 --cmd="set shownoise false" --out=127.0.0.1:20020
mavproxy.exe --master=udpin:127.0.0.1:10030 --target-system=30 --cmd="set shownoise false" --out=127.0.0.1:20030
I assumed that above commands only outputs the target systems one by one but it is not.
When i try to connect the vehicles using below lines of codes:
vehicle1 = connect('127.0.0.1:20010', wait_ready=True)
vehicle2 = connect('127.0.0.1:20020', wait_ready=True)
vehicle3 = connect('127.0.0.1:20030', wait_ready=True)
The incoming and outgoing data traffic is mixing and there is no target_system parameter for connect() function.
How can i connect vehicles one by one without mixing them up?
Thanks...

Start by reproducing the three MAVProxy commands and the Python connect() calls shown in the issue. Trace how each --master, --target-system, and --out endpoint handles incoming and outgoing vehicle traffic, then verify that each connection receives and sends only its intended vehicle's messages without mixing.

Written by the indexing model from the issue text.