fix loading special_tokens_map_file

[ZhiyuanChen]

What does this PR do?

If special tokens map have special specified, e.g.:

SPECIAL_TOKENS_MAP = {
    "pad_token": {
        "content": "<pad>",
        "lstrip": False,
        "normalized": False,
        "rstrip": False,
        "single_word": False,
        "special": True,
    },
}

loading pretrained with special tokens map would complain:

TypeError: tokenizers.AddedToken() got multiple values for keyword argument 'special'

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@ArthurZucker

[ArthurZucker]

Hey! Which version of transformers are you using? Also which tokenizer are you trying to load?
Special map is depracted and only kept for BC

[ZhiyuanChen]

Hey! Which version of transformers are you using? Also which tokenizer are you trying to load? Special map is depracted and only kept for BC

Hi~
I'm using 4.39.3 to load an external tokenizer.
I believe numerous codebase are still keeping the special tokens map like https://huggingface.co/facebook/esm2_t6_8M_UR50D/blob/main/special_tokens_map.json.

[ArthurZucker]

Okay! Could you just rebase on main ?

[ZhiyuanChen]

Okay! Could you just rebase on main ?

One moment

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