chunked/nltk_chunking/tasks_text-to-speech/chunk_68.txt

def is_not_too_long(input_ids):
     input_length = len(input_ids)
     return input_length < 200
dataset = dataset.filter(is_not_too_long, input_columns=["input_ids"])
len(dataset)
8259

Next, create a basic train/test split: 

dataset = dataset.train_test_split(test_size=0.1)

Data collator
In order to combine multiple examples into a batch, you need to define a custom data collator.