block-packages.py

import requests
import pprint

r = requests.get('https://blockchain.info/rawblock/0000000000000000002540e369b106bfd929585e0f059409bd2a956e6a6af79c')
r = r.json()
txs = r['tx']
first = True
packages = []
for i,tx in enumerate(txs):
    if first:
        first = False
        continue
    package = {}
    tx_info = {}

    in_val = 0
    for txin in tx['inputs']:
        in_val += txin['prev_out']['value']
        package_iter = list(packages)
        for p in package_iter:
            if txin['prev_out']['tx_index'] in p:
                if len(package) == 0:
                    package = p
                else:
                    for ptx_hash,ptx_info in p.items():
                        if ptx_hash == 'feerate':
                            continue
                        package[ptx_hash] = ptx_info
                    packages.remove(p)
                
    out_val = 0
    for output in tx['out']:
        out_val += output['value']
    fee = in_val - out_val
    vsize = (tx['weight'] + 3) / 4
    feerate = fee / vsize

    tx_info['hash'] = tx['hash']
    tx_info['feerate'] = feerate
    tx_info['fee'] = fee
    tx_info['vsize'] = vsize
    tx_info['index'] = i
    
    package[tx['tx_index']] = tx_info
    
    tot_fee = 0
    tot_vsize = 0
    for ptx_hash,ptx_info in package.items():
        if ptx_hash == 'feerate':
            continue
        tot_fee += ptx_info['fee']
        tot_vsize += ptx_info['vsize']
    package['feerate'] = tot_fee / tot_vsize
    
    packages.append(package)

pprint.pprint(sorted(packages, key = lambda package: package['feerate']))