Instruction: Describe what context processors are in Flask and how they can be used to inject data into templates.
Context: This question tests the candidate's understanding of Flask's templating features, specifically the use of context processors to make data universally available to all templates.
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Context processors in Flask are essentially functions that run before the template is rendered and inject new variables automatically into the context. This means that these variables can be accessed by any template in the application without the need to explicitly pass them in every view function.
Let me clarify how this works with a straightforward example: Imagine we're building a web application where the user's profile information needs to be accessible on every page, such as the user's name or profile picture. Instead of fetching this data in every view function and passing it to the template, we can create a context processor....