tmp.py

import requests
from pprint import pprint

url = "http://206.189.110.191:9880"

x = {
    "method": "call",
    "params": [0,
               "get_transaction_hex",
               [{"ref_block_num": 34294,
                 "ref_block_prefix": 3707022213,
                 "expiration": "2016-04-06T08:29:27",
                 "operations": [[7,
                                 {"fee": {"amount": 0,
                                          "asset_id": "1.3.0"},
                                  "authorizing_account": "1.2.0",
                                  "account_to_list": "1.2.1",
                                  "new_listing": 1,
                                  "extensions": []}]],
                 "extensions": [],
                 "signatures": ["1f12f0e62577a646a1d0309b3ad083073780462821a364e8205fab19458e9d27b30707052a0ed9ab6d9477da59427ce6c005ca51dff9744431e3e8ec39547e2b10"]}]],
    "jsonrpc": "2.0",
    "id": 6
}

# let's obtain the transaction hex from the ledger node
ret = requests.post(url, json=x).json()
original = ret["result"]

# Let's change the transactions and re-obtain the transaction hex
x["params"][2][0]["operations"][0][1]["account_to_list"] = "1.2.3"
x["params"][2][0]["operations"][0][1]["new_listing"] = 2
ret = requests.post(url, json=x).json()
changed = ret["result"]

print("Original:                 {}".format(original))
print("Changed:                  {}".format(changed))
print("Only Transaction (orig):  {}".format(original[:-130]))
print("Only Transaction (chan):  {}".format(changed[:-130]))
print("Are they equal? {}".format("Yes!" if (original == changed) else "No!"))