Well , I personnaly learned python , and I started learning C recently via openclassroom (https://openclassrooms.com/fr/courses/19980-apprenez-a-programmer-en-c PS : It’s in french)

Here’s an example of python (following BottomText’s comment abou how it’e ez)

PS : You might not understand all of the code or the explication due to the fact that some words aren’t in english and that I don’t explain very well things

PS2: It was the easyest I could fine in my files

PS3: “_” and “-” are tabulations
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def replace(texte):
_texte_inverse = ”
-_for caractere in texte:
_-_if caractere.isupper():
-_-_texte_inverse = texte_inverse + caractere.lower()
_-_elif caractere.islower():
-_-_texte_inverse = texte_inverse + caractere.upper()
_-_else:
-_-_texte_inverse = texte_inverse + caractere

_return texte_inverse

texte = ‘Lorem ipsum; dolor sit amet, consectetur adipiscing elit. Maecenas at enim sed nisl dapibus malesuada at quis eros. Suspendisse eleifend finibus aliquam. Phasellus id ex pellentesque, aliquet urna pharetra, placerat lorem. Donec elementum nibh ac congue consequat. Donec quis massa luctus libero imperdiet viverra eu vel urna. Nulla fermentum ornare justo, vitae pretium tortor blandit ac. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Maecenas faucibus augue in risus vestibulum, et varius eros aliquet. Pellentesque sed ligula et urna consectetur vestibulum vel vitae arcu. Aenean nec eros nunc. Morbi pulvinar lacinia mi, eget condimentum nulla eleifend quis. Donec vehicula ultricies purus, porta ornare turpis congue sed. Aliquam erat volutpat. Nulla varius risus lorem, a auctor metus faucibus nec: Fusce vitae dui euismod nulla rhoncus facilisis sit amet quis felis. ‘

print( replace(texte) )
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def replace(texte): -> def like define , folowed by the function’s name and the parameters between parentheses

texte_inverse = ” -> an empty variable

for charactere in texte: -> for eache characters in the text , do this

if charactere.isupper(): -> if the character is in uppercase , do this

elif charactere.islower(): -> else if the charactere is in lowercase , do this

else: -> I don’t think I need to explain

print(replace(texte)) -> def only define a function , so if you want to test it , you need to print it

texte_inverse = texte_inverse + charactere -> it add the current character in the variable “charactere” (from the “for” line) into texte_inverse
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Even tho it may seems a bit tricky , it isn’t that mutch.