diff --git a/nw/constants/iso.py b/nw/constants/iso.py
index 3efc8c80..069b40fa 100644
--- a/nw/constants/iso.py
+++ b/nw/constants/iso.py
@@ -37,7 +37,6 @@ class isoLanguage():
         "bm" : "Bambara",
         "bn" : "Bengali",
         "bo" : "Tibetan",
-        "bo" : "Tibetan",
         "br" : "Breton",
         "bs" : "Bosnian",
         "ca" : "Catalan",
@@ -46,14 +45,11 @@ class isoLanguage():
         "co" : "Corsican",
         "cr" : "Cree",
         "cs" : "Czech",
-        "cs" : "Czech",
         "cu" : "Church Slavic",
         "cv" : "Chuvash",
         "cy" : "Welsh",
-        "cy" : "Welsh",
         "da" : "Danish",
         "de" : "German",
-        "de" : "German",
         "dv" : "Divehi",
         "dz" : "Dzongkha",
         "ee" : "Ewe",
@@ -63,15 +59,12 @@ class isoLanguage():
         "es" : "Spanish",
         "et" : "Estonian",
         "eu" : "Basque",
-        "eu" : "Basque",
-        "fa" : "Persian",
         "fa" : "Persian",
         "ff" : "Fulah",
         "fi" : "Finnish",
         "fj" : "Fijian",
         "fo" : "Faroese",
         "fr" : "French",
-        "fr" : "French",
         "fy" : "Western Frisian",
         "ga" : "Irish",
         "gd" : "Gaelic",
@@ -87,7 +80,6 @@ class isoLanguage():
         "ht" : "Haitian",
         "hu" : "Hungarian",
         "hy" : "Armenian",
-        "hy" : "Armenian",
         "hz" : "Herero",
         "ia" : "Interlingua",
         "id" : "Indonesian",
@@ -97,13 +89,11 @@ class isoLanguage():
         "ik" : "Inupiaq",
         "io" : "Ido",
         "is" : "Icelandic",
-        "is" : "Icelandic",
         "it" : "Italian",
         "iu" : "Inuktitut",
         "ja" : "Japanese",
         "jv" : "Javanese",
         "ka" : "Georgian",
-        "ka" : "Georgian",
         "kg" : "Kongo",
         "ki" : "Kikuyu",
         "kj" : "Kuanyama",
@@ -130,8 +120,6 @@ class isoLanguage():
         "mg" : "Malagasy",
         "mh" : "Marshallese",
         "mi" : "Maori",
-        "mi" : "Maori",
-        "mk" : "Macedonian",
         "mk" : "Macedonian",
         "ml" : "Malayalam",
         "mn" : "Mongolian",
@@ -173,13 +161,11 @@ class isoLanguage():
         "sg" : "Sango",
         "si" : "Sinhala",
         "sk" : "Slovak",
-        "sk" : "Slovak",
         "sl" : "Slovenian",
         "sm" : "Samoan",
         "sn" : "Shona",
         "so" : "Somali",
         "sq" : "Albanian",
-        "sq" : "Albanian",
         "sr" : "Serbian",
         "ss" : "Swati",
         "st" : "Southern Sotho",
@@ -214,7 +200,6 @@ class isoLanguage():
         "yo" : "Yoruba",
         "za" : "Zhuang",
         "zh" : "Chinese",
-        "zh" : "Chinese",
         "zu" : "Zulu",
     }