diff --git a/rot13_cesa_encryption.py b/rot13_cesa_encryption.py
new file mode 100644
index 0000000..aeb8860
--- /dev/null
+++ b/rot13_cesa_encryption.py
@@ -0,0 +1 @@
+def o(s):return''.join([chr(ord(n)+(13if'Z'<n<'n'or'N'>n else-13))if n.isalpha()else n for n in s])
\ No newline at end of file