flask db init을 치니까
Usage: flask db init [OPTIONS]
Try 'flask db init --help' for help.

Error: While importing 'pybo', an ImportError was raised.
라는 오류가 나오네요.

코드

init.py

from flask import Flask
from flask_migrate import Migrate
from flask_sqlalchemy import SQLAlchemy

import config
db = SQLAlchemy()
migrate = Migrate()

def create_app():
    app = Flask(__name__)
    app.config.from_object(config)

    db.init.app(app)
    migrate.init_app(app, db)

    from .views import main_views
    app.register_blueprint(main_views.bp)

    return app

main_views.py

from flask import Blueprint

bp = Blueprint('main', __name__, url_prefix='/')

@bp.route('/hello')
def hello_pybo():
    return 'Hello, Pybo!'

@bp.route('/')
def index():
    return 'Pybo index'

config.py

import os

BASE_DIR = os.path.dirname(__file__)

SQLALCHEMY_DATABASE_URI = 'sqlite:///{}'.format(os.path.join(BASE_DIR, 'pybo.db'))
SQLALCHEMY_TRACK_MODIFICATIONS = False

IDE : 비주얼 스투디오 코드
파이썬 버전 : 3.8.6 64bit