Download blocks in blk00000.dat format from a specific period

For study purposes, I would like to download blocks from a specific period, i.e. January 2017 – June 2017, in blk.dat format (blk00000.dat, blk*.dat).

I downloaded blockchain.core but it makes me download the whole blockchain – correct me if I’m wrong.

Also I tried with blockchain.info but the problem is that I can only get one block at a time and just in Json or Hex format – don’t need those.

So, do you know how could I do and with which program or API to use?

I’m a beginner, so please the more details you can give the better it is, even if they seems obvious.

For this work I’m coding in python.