Flask is a lightweight WSGI web application framework in Python, designed with simplicity and flexibility in mind. The current version is 3.1.3, released on March 28, 2026, following a regular release cadence with feature and fix updates as needed.
pip install flaskVerified import paths — ran on the pinned version, not inferred.
A minimal Flask application that renders an 'index.html' template when accessing the root URL.
Update your Flask application to handle session changes introduced in version 3.1.3.
Use absolute imports or adjust your project structure to support relative imports properly.
Review application logs for clues about activity before the timeout. Use a debugger to identify infinite loops or deadlocks. Optimize long-running operations or increase the test runner's timeout setting if appropriate. Check for resource leaks or excessive memory/CPU usage.
Install Flask using pip: `pip install Flask`. If using a virtual environment, ensure it is activated before installation.
Manually push an application context using `with app.app_context():` around the code block that requires it.
Ensure that every execution path within a view function explicitly returns a valid Flask response, such as a string, a `render_template()` call, a `jsonify()` response, or a tuple like `('Error message', 400)`.Explicitly specify the allowed HTTP methods in the route decorator using the `methods` argument: `@app.route('/my_route', methods=['GET', 'POST'])`.