translate to python the R code from hackathon

[jralduaveuthey]

check the code from the transformation layer (from the hackathon) and start translate it to python in small functions

[jralduaveuthey]

@jannikrdev @LMSabi please make subtasks and distribute between Laura and you
Example: flagging, logging, ...
NOTE: there is already some python code from the hackathon. Code here https://github.com/correlaid/c7-etl-transform
Probably you should start defining the functions (inputs, outputs) to make them as generic (non cfe-specific) as possible.
The content of the functions can be cfe-specific

[jannikrdev]

Logging can be done with the built-in logging Python module which inherits its config from airflow.
I pushed an architecture proposal for the filtering part to a new branch feat/cleaning. Basically, we have two files: the cleaning.yaml part in which users can define which functions to call on what questions and the cleaning.py dag which will parse the yaml and call the functions accordingly. This way, we would have a quite generic solution while not compromising too much on UX.
Timo suggested using dynamic airflow DAG's, we'll implementing it asap