[EOSIO/eos] Retrieving synced blocks from blocks.log (#5340)

It’s always possible to interpret the blocks.log file, but it would be considerably difficult to do so in Python. You would have to replicate the entirety of fc library variants for the fundamental types, then create Python struct interpretations of every block-related class, including packed transactions and blocks themselves.

It would be considerably easier to enable the mongo_db_plugin, replay your chain, and query your mongodb.

If you’re really determined to read the file yourself, start with `eos/libraries/chain/block_log.cpp` and work your way through the `append()` method and everything it invokes to serialize a block.