The global Keyword

What this Python global-keyword question tests

This question probes whether you understand Python's scoping rules and appreciate the architectural trade-offs around mutable shared state. It is less about syntax and more about reasoning through code clarity, maintainability, and the hidden coupling that careless use of global introduces into a codebase.

Candidates are expected to articulate the practical downsides: how frequent global mutations make data flow harder to trace, complicate testing and refactoring, and create implicit dependencies between functions. The best answers connect these concerns to broader software-engineering principles rather than simply listing language rules.

• Namespace semantics and name resolution in Python
• Side effects and their impact on code readability
• Testing strategies for state-dependent code
• Alternatives: closures, class attributes, dependency injection