Word Count
Easy · Dictionaries
Dicts are great for counting: counts[word] = counts.get(word, 0) + 1 adds 1, starting from 0 for new words. collections.Counter does the same job in one call.
Write a function word_count(text) that returns a dict mapping each word to how many times it appears. Split on whitespace and lowercase every word, so "The" and "the" count as the same word.
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