Word Replacement X47082

Statement

Write a function $replace(ws, x, y)$ that given a list of words $ws$ , and two words $x$ and $y$ , replaces all occurrences of $x$ in $ws$ with $y$ . The function must return two lists: The original list ws and the modified list with the replaced elements (if any).

Sample session

>>> replace(['the', 'cat', 'sat', 'on', 'the', 'mat'], 'cat', 'dog')
(['the', 'cat', 'sat', 'on', 'the', 'mat'], ['the', 'dog', 'sat', 'on', 'the', 'mat'])
>>> replace(['how', 'much', 'wood', 'would', 'a', 'woodchuck', 'chuck', 'if', 'a', 'woodchuck', 'could', 'chuck', 'wood'], 'wood', 'gum')
(['how', 'much', 'wood', 'would', 'a', 'woodchuck', 'chuck', 'if', 'a', 'woodchuck', 'could', 'chuck', 'wood'], ['how', 'much', 'gum', 'would', 'a', 'woodchuck', 'chuck', 'if', 'a', 'woodchuck', 'could', 'chuck', 'gum'])
>>> replace(['how', 'much', 'wood', 'would', 'a', 'woodchuck', 'chuck', 'if', 'a', 'woodchuck', 'could', 'chuck', 'wood'], 'woodchuck', 'beaver')
(['how', 'much', 'wood', 'would', 'a', 'woodchuck', 'chuck', 'if', 'a', 'woodchuck', 'could', 'chuck', 'wood'], ['how', 'much', 'wood', 'would', 'a', 'beaver', 'chuck', 'if', 'a', 'beaver', 'could', 'chuck', 'wood'])
>>> replace(['how', 'much', 'wood', 'would', 'a', 'woodchuck', 'chuck', 'if', 'a', 'woodchuck', 'could', 'chuck', 'wood'], 'groundhog', 'beaver')
(['how', 'much', 'wood', 'would', 'a', 'woodchuck', 'chuck', 'if', 'a', 'woodchuck', 'could', 'chuck', 'wood'], ['how', 'much', 'wood', 'would', 'a', 'woodchuck', 'chuck', 'if', 'a', 'woodchuck', 'could', 'chuck', 'wood'])

Information

Author
Language: English
Official solutions: Python
User solutions: Python