def METHOD_NAME(self):
    tokenizer_w_prefix = self.get_rust_tokenizer(add_prefix_space=True)
    tokenizer_wo_prefix = self.get_rust_tokenizer(add_prefix_space=False)
    tokens_w_prefix = tokenizer_w_prefix.tokenize("Hey")
    tokens_wo_prefix = tokenizer_wo_prefix.tokenize("Hey")
    self.assertNotEqual(tokens_w_prefix, tokens_wo_prefix)