Variable Scope and the `global` keyword Flashcards

What is the output? result = [] for i in range(3): result.append(i) print(i)

Answer: 2

The loop variable i persists in module scope after the loop and holds its last value, 2.

What does the nonlocal keyword do in a nested function?

Answer: Allows the inner function to rebind a variable in the nearest enclosing function's scope

nonlocal targets the nearest enclosing (non-global) scope, letting the inner function modify that variable.

Which of the following correctly modifies a global list inside a function WITHOUT using the global keyword?

Answer: my_list.append(1)

Calling a method like append() mutates the object in place without rebinding the name, so global is not needed.

What is the output? x = 5 def show(): print(x) show() x = 10 show()

Answer: 5 10

Each call to show() reads x from global scope at the time of the call: first 5, then 10.

What is the scope of a variable defined inside an if block at module level?

Answer: Module (global) scope — if blocks don't create a new scope

Python has no block scope; variables created inside if, for, or with blocks belong to the enclosing function or module scope.

What will this code print? def make_counter(): count = 0 def inc(): nonlocal count count += 1 return count return inc c = make_counter() print(c(), c())

Answer: 1 2

nonlocal count lets inc() modify make_counter's count, which persists between calls, yielding 1 then 2.

If a name is not found in local, enclosing, or global scopes, where does Python look next?

Answer: Built-in scope

The final step in LEGB is the built-in scope, which contains names like print, len, and range.