Interpreting the "semi-raw" mode-s data file, and finding which downlink format comes up the most often

data.py

import pyModeS as pm
import matplotlib.pyplot as plt

fig, ax = plt.subplots()

def openFile(filename: str="log.txt") -> list:
    _f = open("log.txt", "r")
    _ls = []
    for _i in _f.readlines():
        _ls.append(_i)
    return _ls

x = openFile()[1:]
instances = {}

for item in x:
    item = item.split(" - ")[1].replace("\n", "")
    key = str(pm.df(item))
    instances[key] = instances.get(key, 0) + 1

print(instances)

Format:
UNIXTIME - HEX