GPT-2 Tokenizer with unmerged digits

A fork of the GPT-2 tokenizer, which removes multi-digit tokens:

from transformers import AutoTokenizer

tokenizer = AutoTokenizer.from_pretrained('cyrilzhang/gpt2-numfix')

tokenizer('123.45')  # [16, 17, 18, 13, 19, 20]
gpt2_tokenizer('123.45')  # [10163, 13, 2231]

Backward-compatible:

tokenizer.decode([10163, 46387])  # '<unused123> pigeon'
gpt2_tokenizer.decode([10163, 46387])  # '123 pigeon'

• This is for my investigations into the arithmetic capabilities of large language models. There is no model here, only a tokenizer.
• PaLM does this. I think it's very reasonable.
• Many models (illustriously, GPT-3) don't do this, because they use the GPT-2 tokenizer.