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01. Define a function that adds two numbersE02. Write a function that returns a greetingE03. Implement a function to find the maximum of threeE04. Create a function to join words with a separatorE05. Write a function that returns the length of a sequenceE06. Implement a function with a default argumentE07. Create a function that accepts any number of argsE08. Write a function that handles keyword argumentsE09. Implement a function that returns multiple valuesE10. Write a function that modifies a passed listE11. Define a function that reads a global variableE12. Write a function with a simple docstringE13. Write a function that demonstrates nonlocal usageM14. Create a function factory returning customized functionsM15. Implement argument unpacking with *args and **kwargsM16. Write a function that avoids mutable default argsM17. Create a function with keyword-only parametersM18. Implement a simple recursive function with a base caseM19. Implement a decorator that logs function callsH20. Write a decorator that memoizes function resultsH

Problem No 11

Define a function that reads a global variable

Easy

≈ 7 minute session

Back to curriculumNext lesson

Summary

Use a module-level global variable inside a function to compute a result.

Problem statement

There is a module-level global variable TAX_RATE representing a tax rate (for example 0.10 for 10%). Define a function apply_tax(price) that reads the global TAX_RATE and returns the price after applying tax (price + price * TAX_RATE). Do not reassign TAX_RATE inside the function — only read its value.

Task

Implement a function that reads a global constant (TAX_RATE) and applies it to an input value.

Examples

Apply 10% tax to 100

Input

apply_tax(100)

Output

110.0

Explanation

With TAX_RATE = 0.1, 100 + 100 * 0.1 = 110.0.

Input format

A numeric price (int or float). The TAX_RATE global variable is defined in the module.

Output format

A numeric result (float) representing the price after tax.

Constraints

Read the global TAX_RATE variable; do not try to re-declare it inside the function. Support integer and float inputs.

Samples

Sample input 0

apply_tax(50.5)

Sample output 0

55.55

Explanation 0

50.5 + 50.5 * 0.1 = 55.55 (with TAX_RATE = 0.1).

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