Develop Reference

Dramatiq uses more than a function

Im currently building a internet scanner which scans ip ranges for the port 25565. When it find a ip with this port open it should ping it to get more info about the port. For that i want to use dramatiq to do it asynchrous, but dramatiq just doesnt work as I expect it. The dramatiq function should only be called if there is a result, but instead the dramatiq worker runs the script(partly).
import json
import masscan
import socket
import dramatiq
import redis
import random
import pymongo
from colorama import Fore,init
from mcstatus import JavaServer
from dramatiq.brokers.redis import RedisBroker
#-------------------------
init()
red = Fore.RED
white = Fore.WHITE
r = redis.Redis()
#-------------------------
client = pymongo.MongoClient("192.168.188.32:27017")
if client.server_info():
print("Connected to MongoDB successfully!")
else:
print("Could not connect to MongoDB.")
db = client["treffer"]
collection = db["ips"]
#-------------------------
#if __name__ == "__main__":
broker = RedisBroker(host="192.168.188.32", port=6379)
dramatiq.set_broker(broker)
print("startet")
#-------------------------
#dramatiq.actor
def mc_and_check_task(ip):
host = JavaServer.lookup(ip)
try:
status = host.status().raw
mc_status = {"ip": str(ip), "status": status}
mc_status_json = json.dumps(mc_status)
x = collection.insert_one(json.loads(mc_status_json))
print(x)
except socket.timeout:
print("Fehler socket.timeout")
except BrokenPipeError:
print("Fehler BrokenPipeError")
except Exception as e:
print(f"An error occurred: + {e}")
#-------------------------
A = list(range(1,255))
B = list(range(1,255))
random.shuffle(A)
random.shuffle(B)
#-------------------------
ip_ranges = []
for a in A:
for b in B:
ip_range = f"{a}.{b}.0.0/16"
ip_ranges.append(ip_range)
#-------------------------
for ip_range in ip_ranges:
print(ip_range)
try:
mas = masscan.PortScanner()
mas.scan(ip_range, ports="25565", arguments="--max-rate 100000")
x = json.loads(mas.scan_result)
len_result = len(x["scan"])
print(len_result)
if len_result > 0:
print(f"Results: {red}{len_result}{white} ")
for ip in x["scan"]:
adresse = ip + ":" + "25565"
mc_and_check_task.send(adresse)
else:
print(f"Results: {white}{len_result}")
except masscan.NetworkConnectionError:
print(f"{ip_range}masscan connection error")
print("done scanning")
When there is a result the worker should get the task to check for more info. But instead it returns this: 132.41.0.0/16 0 Results: 0 done scanning 132.169.0.0/16 0 Results: 0 done scanning 132.222.0.0/16 0 Results: 0 done scanning 213.172.0.0/16 0 Results: 0

Python Socket with Multiprocessing and Pickle issue

I am having a Pickle issue with SSL client to server communication using multiprocessing.
I have an SSL client that connects to the server:
SSLClient.py
import socket
import struct
import ssl
import copyreg
from os import path
import socket
import os
from pathlib import Path
from loguru import logger as log
from utils.misc import read_py_config
from datetime import datetime
from cryptography.fernet import Fernet
fernetkey = '1234567'
fernet = Fernet(fernetkey)
class SSLclient:
license = None
licenseencrypted = None
uuid = None
def __init__(self):
try:
path = Path(__file__).parent / "/lcl" #get unique license key
with path.open() as file:
self.licenseencrypted = file.read().rstrip()
self.license = fernet.decrypt(str.encode(self.licenseencrypted)).decode('ascii')
self.host, self.port = "127.0.0.1", 65416
except Exception as e:
log.error("Could not decode license key")
def connect(self):
self.client_crt = os.path.join(os.path.dirname(__file__), 'key/c-.crt')
self.client_key = os.path.join(os.path.dirname(__file__), 'key/ck-.key')
self.server_crt = os.path.join(os.path.dirname(__file__), 'key/s-.crt')
self.sni_hostname = "example.com"
self._context = ssl.create_default_context(ssl.Purpose.SERVER_AUTH, cafile=self.server_crt)
self._context.load_cert_chain(certfile=self.client_crt, keyfile=self.client_key)
self._sock = None
self._ssock = None
## ---- Client Communication Setup ----
HOST = self.host # The server's hostname or IP address
PORT = self.port # The port used by the server
try:
self._sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self._ssock = self._context.wrap_socket(self._sock, server_side=False, server_hostname=self.sni_hostname)
self._ssock.connect((HOST, PORT))
log.info("Socket successfully created")
except socket.error as err:
log.error("socket creation failed with error %s" %(err))
return False
log.info('Waiting for connection')
return True
def closesockconnection(self):
self._ssock.close()
def checkvalidsite(self):
#check if site is active
jsonobj = {
"uuid": self.license,
"ipaddress" : self.external_ip,
"req": "checkvalidsite"
}
send_msg(self._ssock, json.dumps(jsonobj).encode('utf-8'))
active = False
while True:
Response = recv_msg(self._ssock)
if not Response:
return False
if Response is not None:
Response = Response.decode('utf-8')
Response = json.loads(Response)
req = Response['req']
if req == "checkvalidsite":
active = Response['active']
self.info1 = Response['info1']
self.info2 = Response['info2']
return active
# ---- To Avoid Message Boundary Problem on top of TCP protocol ----
def send_msg(sock: socket, msg): # ---- Use this to send
try:
# Prefix each message with a 4-byte length (network byte order)
msg = struct.pack('>I', len(msg)) + msg
sock.sendall(msg)
except Exception as e:
log.error("Sending message " + str(e))
def recv_msg(sock: socket): # ---- Use this to receive
try:
# Read message length and unpack it into an integer
raw_msglen = recvall(sock, 4)
if not raw_msglen:
return None
msglen = struct.unpack('>I', raw_msglen)[0]
# Read the message data
return recvall(sock, msglen)
except Exception as e:
log.error("Receiving message " + str(e))
return False
def recvall(sock: socket, n: int):
try:
# Helper function to receive n bytes or return None if EOF is hit
data = bytearray()
while len(data) < n:
packet = sock.recv(n - len(data))
if not packet:
return None
data.extend(packet)
return data
except Exception as e:
log.error("Receiving all message " + str(e))
raise Exception(e)
I then have a server that is Multithreaded and accepts the connection and communicates with the client.
Server.py
import socket
import os
from socket import AF_INET, SOCK_STREAM, SO_REUSEADDR, SOL_SOCKET, SHUT_RDWR
import ssl
from os import path
from _thread import *
import struct # Here to convert Python data types into byte streams (in string) and back
import traceback
from threading import Thread
import json
import mysql.connector as mysql
import time
from loguru import logger as log
import threading
from cryptography.fernet import Fernet
fernetkey = '12213423423'
fernet = Fernet(fernetkey)
threadLocal = threading.local()
# ---- To Avoid Message Boundary Problem on top of TCP protocol ----
def send_msg(sock: socket, msg): # ---- Use this to send
try:
# Prefix each message with a 4-byte length (network byte order)
msg = struct.pack('>I', len(msg)) + msg
sock.sendall(msg)
except Exception as e:
log.error("Error send_msg " + str(e))
def recv_msg(sock: socket): # ---- Use this to receive
try:
# Read message length and unpack it into an integer
raw_msglen = recvall(sock, 4)
if not raw_msglen:
return None
msglen = struct.unpack('>I', raw_msglen)[0]
# Read the message data
return recvall(sock, msglen)
except Exception as e:
log.error("Receiving message " + str(e))
return False
def recvall(sock: socket, n: int):
try:
# Helper function to receive n bytes or return None if EOF is hit
data = bytearray()
while len(data) < n:
packet = sock.recv(n - len(data))
if not packet:
return None
data.extend(packet)
return data
except Exception as e:
log.error("Receiving all message " + str(e))
raise Exception(e)
# ---- Server Communication Setup
class Newclient:
def __init__(self):
self.addr = None
self.conn = None
self.uuid = None
class Server:
def __init__(self):
self.HOST = '127.0.0.1' # Standard loopback interface address (localhost)
self.PORT = 65416 # Port to listen on (non-privileged ports are > 1023)
self.ThreadCount = 0
self.threads = []
self.sock = None
def checkvalidsite(self, uuid, ipaddress, cursor, db_connection):
sql = "select * from myexample where uuid ='" + uuid + "'"
cursor.execute(sql)
results = cursor.fetchall()
active = False
for row in results:
active = row["active"]
siteid = row["info1"]
clientid = row["info2"]
return active, siteid, clientid
def Serverthreaded_client(self, newclient):
conn = newclient.conn
try:
while True:
# data = conn.recv(2048) # receive message from client
data = recv_msg(conn)
uuid = None
ipaddress = None
req = None
if not data :
return False
if data is not None:
data = json.loads(data.decode('utf-8'))
uuid = data['uuid']
req = data['req']
if uuid is not None and req is not None:
newclient.uuid = uuid
cursor, db_connection = setupDBConnection()
if req == "checkvalidsite":
ipaddress = data['ipaddress']
active, info1, info2 = self.checkvalidsite(uuid, ipaddress, cursor, db_connection)
data = {
"req": "checkvalidsite",
"uuid": uuid,
"active": active,
"info1" : info1,
"info2" : info2
}
if not data:
break
# conn.sendall(str.encode(reply))
send_msg(conn, json.dumps(data).encode('utf-8'))
log.info("Server response sent")
#conn.close()
closeDBConnection(cursor, db_connection)
else:
#send no message
a=1
except Exception as e:
log.warning(str(e))
log.warning(traceback.format_exc())
finally:
log.info("UUID Closing connection")
conn.shutdown(socket.SHUT_RDWR)
conn.close()
#conn.close()
def Serverconnect(self):
try: # create socket
self.server_cert = path.join(path.dirname(__file__), "keys/server.crt")
self.server_key = path.join(path.dirname(__file__), "keys/server.key")
self.client_cert = path.join(path.dirname(__file__), "keys/client.crt")
self._context = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
self._context.verify_mode = ssl.CERT_REQUIRED
###self._context.load_cert_chain(self.server_cert, self.server_key)
self._context.load_cert_chain(certfile=self.server_cert, keyfile=self.server_key)
###self._context.load_verify_locations(self.client_cert)
self._context.load_verify_locations(cafile=self.client_cert)
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM, 0) ###<-- socket.socket() ???
log.info("Socket successfully created")
except socket.error as err:
log.warning("socket creation failed with error %s" %(err))
try: # bind socket to an address
self.sock.bind((self.HOST, self.PORT))
except socket.error as e:
log.warning(str(e))
log.info('Waiting for a Connection..')
self.sock.listen(3)
def Serverwaitforconnection(self):
while True:
Client, addr = self.sock.accept()
conn = self._context.wrap_socket(Client, server_side=True)
log.info('Connected to: ' + addr[0] + ':' + str(addr[1]))
log.info("SSL established. Peer: {}".format(conn.getpeercert()))
newclient = Newclient()
newclient.addr = addr
newclient.conn = conn
thread = Thread(target=self.Serverthreaded_client, args =(newclient, ))
thread.start()
self.threads.append(newclient)
self.ThreadCount += 1
log.info('Thread Number: ' + str(self.ThreadCount))
def startserver():
server = Server()
server.Serverconnect()
server.Serverwaitforconnection()
serverthread = Thread(target=startserver)
serverthread.daemon = False
serverthread.start()
The server accepts the connection with SSL then waits for a message. It investigates the message command, executes the respective function and returns the data from the database as a response (checkvalidsite in this example).
All good so far (as far as I can tell).
I also have the main program that calls the SSLClient and connects.
Main program
remoteclient = SSLclient()
successfulconnection = remoteclient.connect()
siteactive = remoteclient.checkvalidsite()
So far all is well. However I also have the main program reading in frames from multiple cameras. Can be 20 cameras for example. In order to do this I created multiprocessing to deal with the camera load. Each camera or two cameras per, are assigned to a processor (depending on the number of cores in the machine).
(code below has been stripped out to simplify reading)
x = range(3, 6)
for n in x:
processes = multiprocessing.Process(target=activateMainProgram, args=(queue1, queue2, queue3, queue4, remoteclient, ))
processes.start()
When I try pass the remoteclient (SSLClient) as an argument I get the error:
cannot pickle 'SSLContext' object
I then (after reading online) added the code to the SSLClient:
def save_sslcontext(obj):
return obj.__class__, (obj.protocol,)
copyreg.pickle(ssl.SSLContext, save_sslcontext)
but then I get the error:
cannot pickle 'SSLContext' object
There are 2 options I experimented with:
Trying to get the pickle working (which would be ideal) as the processes themselves each need to communicate with the server. So the processes need to call functions from the SSLClient file. But I cannot get over the pickle issue and can't find a solution online
I then placed the remoteclient = SSLClient code outside the main function. Hoping it would run first and then be accessible to the processes. This worked, however what I learnt was that when a process is called (as it does not share memory) it reprocesses the entire file. Meaning if I have 10 processes each with 2 cameras then I would have 10 connections to the server (1 per process). This means on the server side I would also have 10 threads running each connection. Though it works, it seems significantly inefficient.
Being a noob and self taught in Python I am not sure how to resolve the issue and after 3 days, I figured I would reach out for assistance. If I could get assistance with the pickle issue of the SSLClient then I will have one connection that is shared with all processes and 1 thread in the server to deal with them.
P.s. I have cobbled all of the code together myself and being new to Python if you see that I am totally going down the wrong, incorrect, non-professional track, feel free to yell.
Much appreciated.
Update:
If I change the SSLClient code to:
def save_sslcontext(obj):
return obj.__class__, (obj.protocol,)
copyreg.pickle(ssl.SSLContext, save_sslcontext)
Then I get the error:
[WinError 10038] An operation was attempted on something that is not a socket
Not sure what is better..

Python Port Scanner edit

I've been editing this port scanner for an information security project.
The code works but throws errors (Pycharm Edu) on lines 63 and 34 in that order.
The error message for line 63 is: 'line 63, in
checkhost(target). I've looked at this and can't see why this would throw an error specifically as it is defined on line 34.
The error message for line 34 is: 'NameError: global name 'conf' is not defined'. It's not clear why this is a problem either.
Any help is much appreciated.
The Python code environment is Python 2.7.10
#! /usr/bin/python
from logging import getLogger, ERROR # Import Logging Things
getLogger("scapy.runtime").setLevel(ERROR) # Get Rid if IPv6 Warning
import scapy
import sys
from datetime import datetime # Other stuff
from time import strftime
try:
target = raw_input("[*] Enter Target IP Address: ")
min_port = raw_input("[*] Enter Minumum Port Number: ")
max_port = raw_input("[*] Enter Maximum Port Number: ")
try:
if int(min_port) >= 0 and int(max_port) >= 0 and
int(max_port) >= int(min_port): # Test for valid range of ports
pass
else: # If range didn't raise error, but didn't meet criteria
print "\n[!] Invalid Range of Ports"
print "[!] Exiting..."
sys.exit(1)
except Exception: # If input range raises an error
print "\n[!] Invalid Range of Ports"
print "[!] Exiting..."
sys.exit(1)
except KeyboardInterrupt: # In case the user wants to quit
print "\n[*] User Requested Shutdown..."
print "[*] Exiting..."
sys.exit(1)
ports = range(int(min_port), int(max_port)+1)
start_clock = datetime.now() # Start clock for scan time
SYNACK = 0x12 # Set flag values for later reference
RSTACK = 0x14
def checkhost(target): # Function to check if target is up
conf.verb = 0 # Hide output
try:
ping = sr1(IP(dst = ip)/ICMP()) # Ping the target
print "\n[*] Target is Up, Beginning Scan..."
except Exception: # If ping fails
print "\n[!] Couldn't Resolve Target"
print "[!] Exiting..."
sys.exit(1)
def scanport(port): # Function to scan a given port
try:
srcport = RandShort() # Generate Port Number
conf.verb = 0 # Hide output
SYNACKpkt = sr1(IP(dst = target)/TCP(sport = srcport,
dport = port,flags = "S"))
pktflags = SYNACKpkt.getlayer(TCP).flags
if pktflags == SYNACK: # Cross reference Flags
return True # If open, return true
else:
return False
RSTpkt = IP(dst = target)/TCP(sport = srcport, dport = port,
flags = "R") # Construct RST packet send(RSTpkt)
except KeyboardInterrupt: # In case the user needs to quit
RSTpkt = IP(dst = target)/TCP(sport = srcport, dport = port,
flags = "R") send(RSTpkt)
print "\n[*] User Requested Shutdown..."
print "[*] Exiting..."
sys.exit(1)
checkhost(ip) # Run checkhost() function from earlier
print "[*] Scanning Started at " + strftime("%H:%M:%S") + "!\n"
for port in ports: # Iterate through range of ports
status = scanport(port) # Feed each port into scanning function
if status == True: # Test result
print "Port " + str(port) + ": Open" # Print status
stop_clock = datetime.now() # Stop clock for scan time
total_time = stop_clock - start_clock # Calculate scan time
print "\n[*] Scanning Finished!" # Confirm scan stop
print "[*] Total Scan Duration: " + str(total_time) # Print scan time

The problem is with your import statement, it should
be:
>>> import scapy
>>> from scapy.all import conf
>>> conf.verb = 0
or even better to get rid of possible similar errors in the future
just import scapy as:
>>> from scapy.all import *
>>> conf.verb = 0
Now it should work fine.

Error on socket.recv (Python)

I got a small python program that communicates with an EV3 robot (lego's robot) via BT. The program sends the EV3 a number 1/2 or 3, the robot makes a predefined movement and send back 'A' to indicate that the movement is done and that it is ready for next command.
The system works great but once in a while the python app crushes with this error message:
'An established connection was aborted by the software in your host machine.' this comes from socket.recv that is called inside btListener() thread.
The relevant python parts:
import bluetooth
from gmail import *
import re
from gtts import gTTS
from time import sleep
import pygame
import serial
import thread
import os
import ftplib
from StringIO import StringIO
from blynkapi import Blynk
def a(): #Send 'a' to 'Status' mailbox
print "Send a to robot"
for i in commandA:
client_sock.send(chr(i))
sleep(1)
def b(): # Send 'b' to 'Status' mailbox
def c(): # Send 'c' to 'Status' mailbox
def clear(): # Send clear array to 'Status' mailbox
for i in clearArray:
client_sock.send(chr(i))
def btListener():
# Listen for end of run reply from the EV3
global ev3Flag, listenFlag
while True:
if listenFlag and (not ev3Flag):
try:
data = client_sock.recv(1024) #Check if EV3 is ready for new command
if data[-2] == 'A':
ev3Flag = True
print "Received 'Ready' from EV3 "
sleep(1)
except Exception as e:
print(e)
print "Failed to read data from socket"
def queueHandler():
# Read next command from QueueArray, call sendFunc and clear the queue
global ev3Flag, listenFlag, queueArray
while True:
if len(queueArray) > 0 and ev3Flag:
sendFunc(queueArray[0])
queueArray.pop(0)
def sendFunc(cmd):
#Send the next command on QueueArray to the EV3
global ev3Flag, listenFlag
if cmd == 1:
try:
ev3Flag = False
listenFlag = False
a()
listenFlag = True
sleep(3)
clear() # clear the EV3 btsocket with a default message
except Exception as e:
print "Error on sendFunc cmd = 1"
print(e)
elif cmd == 2:
try:
except Exception as e:
elif cmd == 3:
try:
except Exception as e:
if __name__ == "__main__":
# Blynk setup
blynk = Blynk(auth_token)
switch1 = Blynk(auth_token, pin = "V0")
switch2 = Blynk(auth_token, pin = "V1")
switch3 = Blynk(auth_token, pin = "V2")
print "Blynk connected"
queueArray = [] # Queue array to hold incoming commands
listenFlag = True # Listen to message from EV3
ev3Flag = True # EV3 ready for new command flag
# BT CONNECTION WITH EV3 #
print "Searching for BT connections: "
nearby_devices = bluetooth.discover_devices()
for bdaddr in nearby_devices:
print bdaddr + " - " + bluetooth.lookup_name(bdaddr)
if target_name == bluetooth.lookup_name(bdaddr):
target_address = bdaddr
break
server_sock = bluetooth.BluetoothSocket(bluetooth.RFCOMM)
port = 1
server_sock.bind(("", port))
server_sock.listen(1)
client_sock, address = server_sock.accept()
print "Accepted connection from ", address
if target_address is not None:
print "found target bluetooth device with address ", target_address
else:
print "could not find target bluetooth device nearby"
# END BT CONNECTION WITH EV3 #
try:
thread.start_new_thread(queueHandler, ())
except Exception as e: print(e)
try:
thread.start_new_thread(btListener, ())
except Exception as e: print(e)
while True:
res1 = switch1.get_val()
res2 = switch2.get_val()
res3 = switch3.get_val()
if (int)(res1[0]) == 1:
print "Add 1 to queue"
queueArray.append(1)
if (int)(res2[0]) == 1:
print "Add 2 to queue"
queueArray.append(2)
if (int)(res3[0]) == 1:
print "Add 3 to queue"
queueArray.append(3)
Edit 1:
I tested it a bit more and it seems that the crush happens when the program tries to recv data and send data the same time. (via the clear() or a()/b()/c() functions), could that be the situation?
I'm new to sockets so the first solution that comes in mind is create a flag to limit the action of the socket, is there a better/smarter way to keep that from happening?
Edit 2:
I moved the 'listenFlag = True' line inside sendFunc() to after my call to clear() and it seems to solve the problem which was probably due to the python program trying to receive and sand at the same time.

I moved the 'listenFlag = True' line inside sendFunc() to after my call to clear() and it seems to solve the problem which was probably due to the python program trying to receive and sand at the same time.

Opening 2 serial ports simultaneously in python (one tx one for rx)

I am making a throughput test for a bluetooth link, and I need to send data through a serial port to one bluetooth device which will then transport that data wirelessly to another bluetooth device. The other device will then complete the circuit by sending the data back to the host PC via a different serial port.
The problem seems to be when I attempt to open up 2 different instances of PySerial, the program simply hangs. I have isolated it down to running vs. hanging when I comment out one of the two serial port instantiations. Anyone see a problem with how I'm doing this? If so, what is the proper way to do this? See code below:
#/usr/bin/python
import serial
import time
import sys
DEFAULT_BAUD = 115200
SEND_SIZE = 100
def addPath(file):
pth, fl = os.path.split(__file__)
return os.path.join(pth, file)
def is_number(s):
try:
int(s, 16)
return True
except:
return False
class SerialReader():
def __init__(self, portRx, portTx):
self.portTx = portTx
self.portRx = portRx
self.start_time__sec = time.time()
self.interval__sec = 0
self.buffer = []
self.sendtext = ''.join([str(i) for i in range(SEND_SIZE)])
# send first batch of data
self.portTx.write(self.sendtext)
def didDataArrive(self):
# Read port
self.buffer.extend(list(self.portRx.read(1024)))
# Step through the buffer byte and byte and see if the tick text
# is at the front.
while len(self.buffer) >= len(self.sendtext):
if self.buffer[:len(self.sendtext)] == self.sendtext:
# Discard the tick text
self.buffer = self.buffer[len(self.sendtext):]
# Record time
snapshot__sec = time.time()
self.interval__sec = snapshot__sec - self.start_time__sec
self.start_time__sec = snapshot__sec
# send more data
self.portTx.write(self.sendtext)
return True
else:
self.buffer.pop(0)
return False
def main(port1, port2, baudrate1 = DEFAULT_BAUD, baudrate2 = DEFAULT_BAUD):
try:
import serial
except:
traceback.print_exc()
print "="*60
print "You need to install PySerial"
print "Windows: easy_install pyserial"
print "Mac/Linux: sudo easy_install pyserial"
try:
s1 = serial.Serial(port1, baudrate1, timeout = 0.1)
s2 = serial.Serial(port2, baudrate2, timeout = 0.1)
print "Loading serial ports"
except:
print "Serial port error"
exit()
plot_stop = False
dataread = SerialReader(s2, s1)
try:
while plot_stop == False:
if dataread.didDataArrive():
print dataread.interval__sec
except KeyboardInterrupt:
print "Keyboard Interrupt"
plot_stop = True
finally:
print "Closing"
s1.close()
s2.close()
if __name__ == '__main__':
if (len(sys.argv) < 3):
print "Usage: python extract_data.py phonelink_serialport phonelinkclient_serialport [baudrate1] [baudrate2]"
else:
main(*sys.argv[1:])
If I remove one of the following lines (doesn't matter which one), the python script runs (although it eventually crashes because in the code it eventually tries to reference both ports). If I leave these lines in, the program seems to just hang (it just seems to sit there and run indefinitely):
s1 = serial.Serial(port1, baudrate1, timeout = 0.1)
s2 = serial.Serial(port2, baudrate2, timeout = 0.1)