Change _encode function to encode.

tokenizer.py

@@ -36,7 +36,7 @@ class KmerTokenizer(PreTrainedTokenizer):
         splits = [text[i:i + self.k] for i in range(0, len(text) - self.k + 1, self.stride)]
         return splits
 
-    def _encode(self, text, **kwargs):
+    def encode(self, text, **kwargs):
         tokens = self.tokenize(text, **kwargs)
         token_ids = self.convert_tokens_to_ids(tokens)
         if kwargs.get('return_tensors') == 'pt':