How to specify language codes

Dubbing uses BCP-47 codes for both the source language (spoken in your file) and the target languages you want back. In the REST body those fields are src_lang / target_langs; in the Python SDK they are source_language_code / target_language_codes.

Supported languages

Language	Code
English (India)	`en-IN`
Hindi	`hi-IN`
Bengali	`bn-IN`
Gujarati	`gu-IN`
Kannada	`kn-IN`
Malayalam	`ml-IN`
Marathi	`mr-IN`
Odia	`or-IN`
Punjabi	`pa-IN`
Tamil	`ta-IN`
Telugu	`te-IN`
Assamese	`as-IN`

The same 12 codes are valid for both source and target.

Odia is or-IN for dubbing. od-IN is not accepted, so code that sends od-IN for Odia elsewhere is rejected here with a 422 unprocessable_entity_error.

The source language cannot appear in the target list. Same-language dubbing is not supported, so src_lang: "en-IN" with en-IN among target_langs is rejected with a 422. If you loop over a fixed set of languages, filter the source out before building the request.