input: def generate_web_app() -> str:
      """ Create a Flask web application that takes user input and generates an HTML page with the input.
      The application should have a home route that handles both GET and POST requests. For GET requests, 
      it should render an index.html file. For POST requests, it should retrieve the 'input_text' from the
      form and render a result.html file with the 'input_text' displayed.
      >>> generate_web_app()
      '''
      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')
  
      if __name__ == '__main__':
          app.run(debug=True)
      '''
      """
output:     return '''
      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')
  
      if __name__ == '__main__':
          app.run(debug=True)
      '''