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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 5

Write a function that returns the length of a sequence

Easy

≈ 8 minute session

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Summary

Implement a function that returns the length (number of items) of any iterable or sequence.

Problem statement

Write a function seq_length(seq) that returns the number of items in seq. If seq supports len(seq), use that. If not (for example, a generator), iterate through the iterable and count items. The function should not modify the iterable beyond consuming it when necessary.

Task

Create seq_length(seq) to return how many items are in seq. Support sequences (with len) and general iterables (by iterating).

Examples

List length

Input

seq_length([1, 2, 3])

Output

3

Explanation

The list has three elements.

Input format

One argument: any sequence or iterable.

Output format

An integer representing the number of items.

Constraints

Do not assume all inputs support len(). If len() raises TypeError, count by iterating.

Samples

Sample input 0

seq_length('hello')

Sample output 0

5

Explanation 0

Strings support len(), returning 5.

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