Records and displays information about Zcash blocks.
Copy sendblock.py to /usr/local/bin/sendblock and set it executable.
Add blocknotify=/usr/local/bin/sendblock %s to ~/.zcash/zcash.conf. Restart zcashd.
Run python3 receiveblocks.py. Leave it running in order to collect blocks and build the database.
Run python3 showblocks.py. This is the block observatory user interface, a Python Flask web application. It listens on http://127.0.0.1:8201.