Caesar cipher
Task
The program reads a text and encrypts it with a Caesar cipher with a shift of 2: every letter of the English alphabet is replaced by the letter two places later (a → c, b → d, …). After the end of the alphabet it wraps around: y → a, z → b.
Upper-case letters stay upper-case (Z → B). All other characters - spaces, digits, punctuation and letters with diacritics - stay unchanged.
Examples
Input
ahoj svet
Expected output
cjql uxgv
After you submit, 4 hidden tests will also check your solution: the end of the alphabet, upper case and punctuation, digits and a dot, letters with diacritics.
Python starts the first time you run code.
Ctrl+Enter runs the program. Tab indents. Press Esc, then Tab, to leave the editor.
Input (stdin)
Each line = one call to input().
Output
Hints
Try it yourself first. Each hint reveals a little more - and lowers the reward a little.
Signed out, hints are free - but no XP is awarded either.
Solution
The solution unlocks after the last hint.