def create_a_room(self, ev):
    if not self.in_new_window:
        if len(self.room_list) > 5:
            messagebox.showwarning("Can't create", "There is maximum of rooms already(6/6)")
            return
        self.create_room_window = CreateWindow()
        self.in_new_window = True
        self.create_room_window.start()
        self.wait_window(self.create_room_window)
        self.in_new_window = False
        created_room = self.create_room_window.get_created_room()
        if not created_room:
            return
        self.launching_room(created_room)