one-py | Python Object Model and COM Interface Wrapper | Wrapper library

I'm running RabbitMQ, in a Docker container (rabbitmq:3-management image) as part of a Docker Compose application. The application contains some ASP.NET Core WebApi microservices, which exchange messages via this broker. That works fine and didn't give me any problems so far.

Now I need to publish messages from a Python application to an exchange/queue which was created from one of the ASP.NET Core microservices. The microservice contains a consumer for this queue. For publishing from python, I'm using pika. The problem is, I can't seem to get the publishing right. Whenever I execute my Python script, I can see in the RabbitMQ management UI that a new exchange and queue with the suffix "_skipped" were created. It seems as if my message was sent there instead of the actual queue. Also, when trying to publish directly from the management UI, the message actually makes it to the microservice, but there I'll get an exception, that the message could not be deserialized to a MassTransit envelope object, and also a new exchange and queue with the "_error" suffix.

I have no idea where the problem is. I think the exchange/queue themselves are fine, since other queues/consumers/publishers for microservice to microservice communication in this project work. So then it's probably either how I'm trying to address the exchange/queue from Python, or something with my message body which is not right.

This page gives some info about how messages need to be structured, but not too detailed, and here I got most of the info about how to publish with Python.

Below you see the relevant code regarding the host/queue configuration in the microservice, as well as the Python script. Any help/tips on how I can get this to work would be greatly appreciated.

ASP.NET Core:

In my previous post, we found a way to pass an image file from one python to another: pass video data from one python script to another

I am now trying to pass a video (successive images):

write.py

a very green python user here, so go easy on me and the docs haven't helped me understand what I'm missing. Similar to RE split multiple arguments | (or) returns none python, I need to split a string on multiple delimiters. The above question only allows either keeping none or keeping both delimiters - I need to keep only one of them. Note that the above question was from 2012, so likely a much earlier version of Python that 3.6, which I'm using.

My data: