input: 
  from flask import Flask, render_template, request
  
  app = Flask(__name__)
  
  @app.route('/', methods=['GET', 'POST'])
  def home():
      """
      Create a web application in Flask that takes user input through a form and generates an HTML page displaying the input.
      >>> # No direct test case output as it's a web app, but the app should display the user input on '/result.html' when the form is submitted.
      """
      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 render_template('index.html')
  
  if __name__ == '__main__':
      app.run(debug=True)
  