To convert a list into a set in Python, you can use the set() constructor. It takes an iterable, such as a list, as an argument and creates a new set containing the unique elements from the list.

In Django, you create new URL patterns by adding them to the urls.py file of your app. This file maps URLs to view functions, allowing you to define the routing of your web application.

In Python, the pdb module is used for debugging. It allows you to set breakpoints, step through code, and inspect variable values during program execution.

In Python, to define a generator, you use the yield keyword within a function. A generator function produces an iterator, which can be used to generate a sequence of values lazily, conserving memory and improving performance.

To define a metaclass, you generally override the __new__ method. This method is responsible for creating the class itself and can be customized to modify class attributes and behavior during creation.

To enable database migrations in Flask, the Flask-Migrate extension is used. Flask-Migrate is an extension that integrates the Alembic database migration framework with Flask applications, allowing you to manage database schema changes easily.

To find the shortest path in a graph with non-negative edge weights, you can use Dijkstra's algorithm. This algorithm efficiently calculates the shortest path from a source vertex to all other vertices in a weighted graph.

To obtain all the keys from a Python dictionary, you should use the keys() method. This method returns a view object that displays a list of all the keys in the dictionary.

In Python, to represent a constant property in a class, you would typically use the readonly keyword. It ensures that the property cannot be modified after it's assigned a value.

In Python, the __new__ method in a metaclass is executed when a new class is created. It allows you to customize the creation process of classes before __init__ is called.