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diff --git a/challenge-025/lubos-kolouch/python/ch-2.py b/challenge-025/lubos-kolouch/python/ch-2.py
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+def chaocipher_encrypt(message: str) -> str:
+    """
+    Encrypts a message using the Chaocipher algorithm.
+
+    Chaocipher is a symmetric encryption algorithm that uses two mixed alphabets to
+    perform a double substitution on each letter of the plaintext. The two alphabets
+    are predetermined and fixed.
+
+    Args:
+        message: The message to be encrypted.
+
+    Returns:
+        The encrypted message.
+    """
+    # Define the Chaocipher alphabets
+    left_alphabet = "HXUCZVAMDSLKPEFJRIGTWOBNYQ"
+    right_alphabet = "PTLNBQDEOYSFAVZKGJRIHWXUMC"
+
+    ciphertext = ""
+    left_index = 0
+    right_index = 0
+
+    # Loop through each character in the message
+    for char in message.upper():
+        if not char.isalpha():
+            # Ignore non-alphabetic characters
+            ciphertext += char
+            continue
+
+        # Find the index of the character in the left alphabet
+        left_char_index = left_alphabet.index(char)
+
+        # Swap the left and right indices
+        left_index, right_index = right_index, left_index
+
+        # Find the corresponding character in the right alphabet
+        right_char_index = (left_char_index + right_index) % 26
+        right_char = right_alphabet[right_char_index]
+
+        # Append the encrypted character to the ciphertext
+        ciphertext += right_char
+
+    return ciphertext
+
+
+def chaocipher_decrypt(ciphertext: str) -> str:
+    """
+    Decrypts a message that has been encrypted using the Chaocipher algorithm.
+
+    Args:
+        ciphertext: The message to be decrypted.
+
+    Returns:
+        The decrypted message.
+    """
+    # Define the Chaocipher alphabets
+    left_alphabet = "HXUCZVAMDSLKPEFJRIGTWOBNYQ"
+    right_alphabet = "PTLNBQDEOYSFAVZKGJRIHWXUMC"
+
+    plaintext = ""
+    left_index = 0
+    right_index = 0
+
+    # Loop through each character in the ciphertext
+    for char in ciphertext.upper():
+        if not char.isalpha():
+            # Ignore non-alphabetic characters
+            plaintext += char
+            continue
+
+        # Find the index of the character in the right alphabet
+        right_char_index = right_alphabet.index(char)
+
+        # Swap the left and right indices
+        left_index, right_index = right_index, left_index
+
+        # Find the corresponding character in the left alphabet
+        left_char_index = (right_char_index - right_index) % 26
+        left_char = left_alphabet[left_char_index]
+
+        # Append the decrypted character to the plaintext
+        plaintext += left_char
+
+    return plaintext
+
+
+# Example usage
+message = "Hello World!"
+ciphertext = chaocipher_encrypt(message)
+print(f"Ciphertext: {ciphertext}")
+plaintext = chaocipher_decrypt(ciphertext)
+print(f"Plaintext: {plaintext}")