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diff --git a/‎ciphers/baconian_cipher.py‎
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+"""
+Program to encode and decode Baconian or Bacon's Cipher
+Wikipedia reference : https://en.wikipedia.org/wiki/Bacon%27s_cipher
+"""
+
+encode_dict = {
+    "a": "AAAAA",
+    "b": "AAAAB",
+    "c": "AAABA",
+    "d": "AAABB",
+    "e": "AABAA",
+    "f": "AABAB",
+    "g": "AABBA",
+    "h": "AABBB",
+    "i": "ABAAA",
+    "j": "BBBAA",
+    "k": "ABAAB",
+    "l": "ABABA",
+    "m": "ABABB",
+    "n": "ABBAA",
+    "o": "ABBAB",
+    "p": "ABBBA",
+    "q": "ABBBB",
+    "r": "BAAAA",
+    "s": "BAAAB",
+    "t": "BAABA",
+    "u": "BAABB",
+    "v": "BBBAB",
+    "w": "BABAA",
+    "x": "BABAB",
+    "y": "BABBA",
+    "z": "BABBB",
+    " ": " ",
+}
+
+
+decode_dict = {value: key for key, value in encode_dict.items()}
+
+
+def encode(word: str) -> str:
+    """
+    Encodes to Baconian cipher
+
+    >>> encode("hello")
+    'AABBBAABAAABABAABABAABBAB'
+    >>> encode("hello world")
+    'AABBBAABAAABABAABABAABBAB BABAAABBABBAAAAABABAAAABB'
+    >>> encode("hello world!")
+    Traceback (most recent call last):
+        ...
+    Exception: encode() accepts only letters of the alphabet and spaces
+    """
+    encoded = ""
+    for letter in word.lower():
+        if letter.isalpha() or letter == " ":
+            encoded += encode_dict[letter]
+        else:
+            raise Exception("encode() accepts only letters of the alphabet and spaces")
+    return encoded
+
+
+def decode(coded: str) -> str:
+    """
+    Decodes from Baconian cipher
+
+    >>> decode("AABBBAABAAABABAABABAABBAB BABAAABBABBAAAAABABAAAABB")
+    'hello world'
+    >>> decode("AABBBAABAAABABAABABAABBAB")
+    'hello'
+    >>> decode("AABBBAABAAABABAABABAABBAB BABAAABBABBAAAAABABAAAABB!")
+    Traceback (most recent call last):
+        ...
+    Exception: decode() accepts only 'A', 'B' and spaces
+    """
+    if set(coded) - {"A", "B", " "} != set():
+        raise Exception("decode() accepts only 'A', 'B' and spaces")
+    decoded = ""
+    for word in coded.split():
+        while len(word) != 0:
+            decoded += decode_dict[word[:5]]
+            word = word[5:]
+        decoded += " "
+    return decoded.strip()
+
+
+if "__name__" == "__main__":
+    from doctest import testmod
+
+    testmod()