text: 
  from flask import Flask, render_template, request
  from wtforms import Form, TextAreaField, validators
  
  app = Flask(__name__)
  
  class HelloForm(Form):
      sayhello = TextAreaField('',[validators.DataRequired()])
  
  # 시작페이지에 텍스트필드 추가
  @app.route('/')
  def index():
      form = HelloForm(request.form)
      return render_template('first_app.html', form=form)
  
  # html 폼으로 전달된 내용을 검증한 후 hello.html 페이지를 출력
  @app.route('/hello', methods=['POST'])
  def hello():
      form = HelloForm(request.form)
      if request.method == 'POST' and form.validate():
          name = request.form['sayhello']
          return render_template('hello.html', name=name)
      return render_template('first_app.html', form=form)
  
  if __name__ == '__main__':
      app.run(debug=True)
  