new file: Lösung Kata Caesar Cipher Helper

src/caesar_cipher_helper

@@ -0,0 +1,39 @@
+"""
+Lösung des Katas: Caesar Cipher Helper
+Link: https://www.codewars.com/kata/526d42b6526963598d0004db
+"""
+
+
+beginning_alphabet = ord("A")
+ending_alphabet = ord("Z")
+
+class CaesarCipher(object):
+    def __init__(self, offset):
+        self.offset = offset
+
+    def encode(self, st):
+        upper = st.upper()
+        encoded_st = ""
+        for char in upper:
+            if beginning_alphabet <= ord(char) <= ending_alphabet:
+                encoded_char = (ord(char) + self.offset)
+                if encoded_char > ending_alphabet:
+                    encoded_char -= (ending_alphabet - (beginning_alphabet - 1))
+                encoded_st += chr(encoded_char)
+            else:
+                encoded_st += char
+
+        return encoded_st
+
+    def decode(self, st):
+        decoded_st = ""
+        for char in st:
+            if beginning_alphabet <= ord(char) <= ending_alphabet:
+                decoded_char = (ord(char) - self.offset)
+                if decoded_char < beginning_alphabet:
+                    decoded_char += (ending_alphabet - (beginning_alphabet - 1))
+                decoded_st += chr(decoded_char)
+            else:
+                decoded_st += char
+
+        return decoded_st