The benefits we will have by moving it into a a separate script are:
1) Not embedding the script inside Jenkins - We want to move to pipeline jobs in the future and in that matter we want to embed code in yamls as little as possible.
The way to do it is to move the upstream_source_collector.py to a seperate script that'll be called from a jenkins step.
The only embedded code will be a very short and simple code that'll get the script from upstream before actually calling it.

2) use the script as command line tool - When developers wants to run it locally on their cloned D/S projects.

3) Use hash as U/S projects folders - When using as command line tool, avoid looking for a way to match D/S to its U/S corresponding.
Hashing means, hash the URL of the U/S repo and name the folder you are going to clone into with the hash code.
That way, U/S folder name will be by the hash of the rep URL in the upstream_sources.yaml file.
Another benefit will be the fact that we will never use two copies of U/S clone to two different D/S repos that their U/S repo is the same