Question to the community: does anyone know a free API to do a backtest with Python? The idea behind it is to track a portfolio retrospectively. Example:

Purchase $BATS (+0,78 %) monthly 50€ start 01.01.2020 to 01.11.2024. Listing month by month performance and dividend. Total overview at the end. Gladly by PM if someone knows a free API.

Thank you