pubsub library for python

pubsub.py

#!/usr/bin/env -S python3 -u
I_PREFER_MULTI_THREADING=1

if I_PREFER_MULTI_THREADING:
    from threading import Thread, Lock, Event
    from queue import Queue
else:
    from multiprocessing import Process as Thread, Lock, Event, Queue

from time import sleep
from subprocess import Popen, PIPE

SEE_DEBUG=True

trigger = Event()
pager = Event()

def process_out(q,qp,fd, pager):
    anchor_seen=False 
    while True:
        with Lock():
            line=fd.readline().rstrip("\n")
            if line.strip("\r") and anchor_seen \
                and (SEE_DEBUG or not line.startswith("#")):
                q.put([line])
                qp.put([line])
            anchor_seen|= anchor_seen or line == "BEGINNING!"
        if callback:
            pager.set()
        sleep(.001)

def process_in(q,fd, trigger):
    while True:
        trigger.wait()
        line=q.get()
        fd.write(line+"\n")
        fd.flush()

qin=Queue()
qout=Queue()
qcallback=Queue()
def callback(qout, pager):
    while True:
        pager.wait()
        while not qout.empty():
            line = qout.get()
            for l in line:
                if "general" not in l:
                    print("*" + l)

def pubsub(qin=qin, qout=qout,host="pubsub.home.", port=2023, user="pubsub",
        pwd="pubsub", client_cert="./client.pem", server_ca="./server.crt",
        callback=None, pager=None):
    p = Popen(
        f"socat - OPENSSL-CONNECT:{host}:{port},cert={client_cert},cafile={server_ca}".split(" "),
        stdout=PIPE, stdin=PIPE,encoding='utf-8')
    if callback:
        assert pager
        callb = Thread(target=callback, args=(qcallback, pager))
        callb.start()
    reader=Thread(target=process_out, args=(qout, qcallback,p.stdout, pager))
    writer=Thread(target=process_in, args=(qin, p.stdin,trigger))
    reader.start()
    writer.start()
    sleep(2)
    p.stdin.write(user + "\n")
    p.stdin.flush()
    sleep(2)
    p.stdin.write(pwd + "\n")
    p.stdin.flush()

def send(line):
    with Lock():
        qin.put(line)
        trigger.set()

def collect():
    res= []
    while not qout.empty():
        res+=qout.get()
    return res


pubsub(
    qin, qout,"pubsub.home.", 2023, "pubsub", "pubsub","./client.pem",
    "./server.crt",callback, pager
)