input: def create_flask_app() -> Flask:
      """
      Create a simple Flask web application that takes user input via a form and generates an HTML page displaying the input.
  
      >>> app = create_flask_app()
      >>> app.run() # This will start a local development server that listens for incoming requests
      """
      from flask import Flask, render_template, request
  
      app = Flask(__name__)
  
      @app.route('/', methods=['GET', 'POST'])
      def home():
          if request.method == 'POST':
              input_text = request.form.get('input_text')
              return render_template('result.html', input_text=input_text)
          return render_template('index.html')
  
      return app
  
  if __name__ == '__main__':
      app = create_flask_app()
      app.run(debug=True)
output:     @app.route('/result', methods=['GET'])
      def result():
          input_text = request.args.get('input_text')
          return render_template('result.html', input_text=input_text)