input: from flask import Flask, render_template, request
  
  app = Flask(__name__)
  
  @app.route('/', methods=['GET', 'POST'])
  def home():
      """
      This function creates a Flask web application that takes user input and generates an HTML page with the input.
      If the request method is POST, it retrieves the input from the form and renders the 'result.html' template with the input.
      If the method is GET, it renders the 'index.html' template.
      >>> # Assuming 'index.html' has a form with input named 'input_text'
      >>> # and this is the contents of 'result.html':
      >>> # <html><body><h1>Your Input: </h1><p>{{input_text}}</p></body></html>
      >>> home() # Triggers GET request
      ''
      >>> home() # Triggers POST request with form data input_text='Hello'
      '<html><body><h1>Your Input: </h1><p>Hello</p></body></html>'
      """
      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:     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')