freecodecamp--freecodecamp/curriculum/challenges/english/blocks/daily-coding-challenges-python/68b06e589bf2273243814773.md

id, title, challengeType, dashedName

id	title	challengeType	dashedName
68b06e589bf2273243814773	Challenge 37: Sentence Capitalizer	29	challenge-37

--description--

Given a paragraph, return a new paragraph where the first letter of each sentence is capitalized.

• All other characters should be preserved.
• Sentences can end with a period (.), one or more question marks (?), or one or more exclamation points (!).

--hints--

capitalize("this is a simple sentence.") should return "This is a simple sentence.".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(capitalize("this is a simple sentence."), "This is a simple sentence.")`)
}})

capitalize("hello world. how are you?") should return "Hello world. How are you?".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(capitalize("hello world. how are you?"), "Hello world. How are you?")`)
}})

capitalize("i did today's coding challenge... it was fun!!") should return "I did today's coding challenge... It was fun!!".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(capitalize("i did today's coding challenge... it was fun!!"), "I did today's coding challenge... It was fun!!")`)
}})

capitalize("crazy!!!strange???unconventional...sentences.") should return "Crazy!!!Strange???Unconventional...Sentences.".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(capitalize("crazy!!!strange???unconventional...sentences."), "Crazy!!!Strange???Unconventional...Sentences.")`)
}})

capitalize("there's a space before this period . why is there a space before that period ?") should return "There's a space before this period . Why is there a space before that period ?".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(capitalize("there's a space before this period . why is there a space before that period ?"), "There's a space before this period . Why is there a space before that period ?")`)
}})

--seed--

--seed-contents--

def capitalize(paragraph):

    return paragraph

--solutions--

import re
def capitalize(paragraph):
    def repl(match):
        return match.group(1) + match.group(2) + match.group(3).upper()

    result = re.sub(r'([.!?]+)(\s*)([a-z])', repl, paragraph)

    if result and result[0].islower():
        result = result[0].upper() + result[1:]

    return result