Solution
# ask the user for some text
text = input('Please enter a word or phrase: ')
# use the .swapcase() string method to swap uppercase with lowercase and vice versa
print(text.swapcase())Output
Enter a word or phrase: HeLlO wOrLd
hElLo WoRlD
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Enter a word or phrase: UPPER lower
upper LOWER
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Enter a word or phrase: supERCaliFRagIliSticEXpiAliDoCIOus
SUPercALIfrAGiLIsTICexPIaLIdOcioUS
Keep in mind that this is just one potential solution.