# Custom PostProcessor?

**URL:** </static-proxy?url=https%3A%2F%2Fdiscuss.huggingface.co%2Ft%2Fcustom-postprocessor%2F25847%3E%5C
**Category:** 🤗Tokenizers\
**Created:** [November 10, 2022, 6:46am UTC](/static-proxy?url=https%3A%2F%2Fdiscuss.huggingface.co%2Ft%2Fcustom-postprocessor%2F25847 "2022-11-10T06:46:40Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![tonyswoo](https://avatars.discourse-cdn.com/v4/letter/t/e495f1/32.png) [@tonyswoo](/static-proxy?url=https%3A%2F%2Fdiscuss.huggingface.co%2Fu%2Ftonyswoo)%5C
**Post date:** [November 10, 2022, 6:46am UTC](/static-proxy?url=https%3A%2F%2Fdiscuss.huggingface.co%2Ft%2Fcustom-postprocessor%2F25847%2F1 "2022-11-10T06:46:40Z")

</div>

Is there a way to implement a custom post-processor?

On this forum, I did see people discussing [how to implement a custom pre-tokenizer and normalizer](/static-proxy?url=https%3A%2F%2Fdiscuss.huggingface.co%2Ft%2F1637)%2C but I haven’t seen any posts discussing the post-processor.

My first guess was to subclass `PostProcessor` and implement `num_special_tokens_to_add` and `process`, but trying to initialize the subclass just gives a `TypeError: No constructor defined`.  
(Assuming it has something to do with the Rust-Python binding and not having a ` __new__ ` method)

So, does the HuggingFace tokenizers library support custom post-processing? If so, is there any instruction or example code available?

Thank you.