python from flask import Flask app = Flask(__name__) @app.route('/') def index(): return 'Hello, Flask!' if __name__ == '__main__': app.run() python from flask import Flask, request app = Flask(__name__) @app.route('/login', methods=['POST']) def login(): username = request.form.get('username') password = request.form.get('password') return 'Login successful' if __name__ == '__main__': app.run() python from flask import Flask, render_template, jsonify app = Flask(__name__) @app.route('/') def index(): return 'Hello, Flask!' @app.route('/user') def get_user(): user = { 'name': 'John Doe', 'age': 25, 'email': 'johndoe@example.com' } return jsonify(user) @app.route('/template') def show_template(): return render_template('template.html', name='Flask') if __name__ == '__main__': app.run()