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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 4

Create a function to join words with a separator

Easy

≈ 6 minute session

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Summary

Write a function that joins a sequence of items into a single string using a provided separator.

Problem statement

Create a function join_with_separator(words, sep) that takes an iterable of items (strings, numbers, etc.) and a separator string sep. The function should convert each item to its string representation and join them with the separator. If the iterable is empty, return an empty string. The function must accept lists, tuples, and other iterables.

Task

Implement join_with_separator(words, sep) that converts items to strings and joins them with sep. Handle empty sequences and different iterable types.

Examples

Join words with a space

Input

join_with_separator(['hello', 'world'], ' ')

Output

hello world

Explanation

Each item is a string; they are joined with a single space.

Input format

An iterable (list/tuple/other) of items as the first argument and a string separator as the second argument.

Output format

A single string containing the joined items.

Constraints

Do not assume all items are strings. Convert items to strings before joining. The separator is always a string.

Samples

Sample input 0

join_with_separator(['a', 'b', 'c'], ',')

Sample output 0

a,b,c

Explanation 0

The list items are joined by a comma.

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