def set_db():
    myclient = connect_db()
    message = "Select Database"
    banner(message)
    today = datetime.today()
    today = today.strftime("%m-%d-%Y")
    print(Fore.CYAN + "Available MongoDB Databases:")
    if myclient != None:
        # the list_database_names() method returns a list of strings
        database_names = myclient.list_database_names()
        counter = 1
        for db in database_names:
            message = str(counter) + '. ' + db
            print(message)
            counter = counter + 1
    print ("There are", len(database_names), "databases.\n")
    print(f"Please select a database. Enter a number 1 through {len(database_names)}.")
    choice = input("Enter a number: ")
    if is_digit(choice) == True:
        if int(choice) > counter:
            print("Wrong selection.")
            set_db()
        choice = int(choice)
        choice = choice - 1
        mydb = database_names[choice]
        #mydb = myclient['aws_ec2_list']
        print(f"You've selected: {mydb}\n")
    else:
        print("Must enter a digit. Try again.\n")
        set_db()
    mydb = myclient['aws_ec2_list']
    instance_col = 'ec2_list-' + today
    instance_col = mydb[instance_col]
    return mydb, instance_col