How to merge data (CSV) files from multiple branches (Git and DVC)?

Question

Background: In my projects I'm using GIT and DVC to keep track of versions:

• GIT - only for source codes
• DVC - for dataset, model objects and outputs

I'm testing different approaches in separate branches, i.e:

• random_forest
• neural_network_1
• ...

Typically as an output I'm keeping predictions in csv file with standarised name (i.e.: pred_test.csv). As a consequence in different branches I've different pred_test.csv files. The structure of the file is very simple, it contains two columns:

• ID
• Prediction

Question: What is the best way to merge those prediction files into single big file?

I would like to obtain a file with structure:

• ID
• Prediction_random_forest
• Prediction_neural_network_1
• Prediction_...

My main issue is how to access files with predictions which are in different branches?