old_contents: import socket
  import json
  
  usrLogin = 'D'
  usrPass = 'q'
  
  try:
      with open('usersDB.txt', 'r+') as f:
          usersDB = json.loads(f.read())
  
      sock = socket.socket()  # Конфиг
      sock.bind(('', 9090))
      sock.listen(1)
  
      print('Server started')  # Приём соединения
      conn, addr = sock.accept()
      print('connected:', addr)
  
      while True:
          data = conn.recv(1024)  # Логин
          login = data.decode()
          print(login)
          if login in usersDB:
              status = 'OK'
          else:
              status = 'ERR'
          conn.send(status.encode())
          if status == 'OK':
              break
  
      while True:
          data = conn.recv(1024)  # Пароль
          password = data.decode()
          print(password)
          if password == usersDB[login]:
              status = 'OK'
          else:
              status = 'ERR'
          conn.send(status.encode())
          if status == 'OK':
              break
  
      with open(login+'.txt', 'r+') as f:  # Отправка архива сообщений
          data = f.read()
          conn.send(data.encode())
          msgDB = json.loads(data)
  
      while True:
          data = conn.recv(1024)  # Получение сообщений
          msg = data.decode()
          print(msg)
          msgDB.append(msg)
          if msg == 'exit':
              break
  
      with open('q', 'r+') as f:
          f.write(json.dumps(msgDB))
      conn.close()
  except:
      print('Oops, something went wrong')
  
new_contents: import socket
  import json
  
  usrLogin = 'D'
  usrPass = 'q'
  
  while True:
      try:
          with open('usersDB.txt', 'r+') as f:
              usersDB = json.loads(f.read())
  
          sock = socket.socket()  # Конфиг
          sock.bind(('', 9090))
          sock.listen(1)
  
          print('Server started')  # Приём соединения
          conn, addr = sock.accept()
          print('connected:', addr)
  
          while True:
              data = conn.recv(1024)  # Логин
              login = data.decode()
              print(login)
              if login in usersDB:
                  status = 'OK'
              else:
                  status = 'ERR'
              conn.send(status.encode())
              if status == 'OK':
                  break
  
          while True:
              data = conn.recv(1024)  # Пароль
              password = data.decode()
              print(password)
              if password == usersDB[login]:
                  status = 'OK'
              else:
                  status = 'ERR'
              conn.send(status.encode())
              if status == 'OK':
                  break
  
          with open(login+'.txt', 'r+') as f:  # Отправка архива сообщений
              data = f.read()
              conn.send(data.encode())
              msgDB = json.loads(data)
  
          while True:
              data = conn.recv(1024)  # Получение сообщений
              msg = data.decode()
              print(msg)
              msgDB.append(msg)
              if msg == 'exit':
                  break
  
          with open(login+'.txt', 'r+') as f:
              f.write(json.dumps(msgDB))
          conn.close()
      except:
          print('Oops, something went wrong')
  
subject: Update v1