Add UL2 code

.gitattributes

@@ -30,3 +30,4 @@ saved_model/**/* filter=lfs diff=lfs merge=lfs -text
 *.zip filter=lfs diff=lfs merge=lfs -text
 *.zst filter=lfs diff=lfs merge=lfs -text
 *tfevents* filter=lfs diff=lfs merge=lfs -text
+checkpoint*/** filter=lfs diff=lfs merge=lfs -text

.gitignore

@@ -0,0 +1 @@
+__pycache__/

config.gin

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+from __gin__ import dynamic_registration
+import __main__ as train_script
+import seqio
+from t5x import adafactor
+from t5x.examples.t5 import network
+from t5x import gin_utils
+from t5x import models
+from t5x import partitioning
+from t5x import trainer
+from t5x import utils
+import tasks
+
+# Macros:
+# ==============================================================================
+BATCH_SIZE = 256
+DROPOUT_RATE = 0.0
+LABEL_SMOOTHING = 0.0
+LOSS_NORMALIZING_FACTOR = None
+MIXTURE_OR_TASK_MODULE = None
+MIXTURE_OR_TASK_NAME = 'pretrain_finnish_ul2'
+MODEL = @models.EncoderDecoderModel()
+MODEL_DIR = '/researchdisk/ul2-small-nl16-finnish'
+OPTIMIZER = @adafactor.Adafactor()
+RANDOM_SEED = None
+SHUFFLE_TRAIN_EXAMPLES = True
+TASK_FEATURE_LENGTHS = {'inputs': 512, 'targets': 512}
+TRAIN_STEPS = 500000
+USE_CACHED_TASKS = False
+USE_HARDWARE_RNG = False
+VOCABULARY = @seqio.SentencePieceVocabulary()
+Z_LOSS = 0.0001
+
+# Parameters for adafactor.Adafactor:
+# ==============================================================================
+adafactor.Adafactor.decay_rate = 0.8
+adafactor.Adafactor.logical_factor_rules = \
+    @adafactor.standard_logical_factor_rules()
+adafactor.Adafactor.step_offset = 0
+
+# Parameters for utils.CheckpointConfig:
+# ==============================================================================
+utils.CheckpointConfig.restore = @utils.RestoreCheckpointConfig()
+utils.CheckpointConfig.save = @utils.SaveCheckpointConfig()
+
+# Parameters for utils.create_learning_rate_scheduler:
+# ==============================================================================
+utils.create_learning_rate_scheduler.base_learning_rate = 1.0
+utils.create_learning_rate_scheduler.factors = 'constant * rsqrt_decay'
+utils.create_learning_rate_scheduler.warmup_steps = 10000
+
+# Parameters for train/utils.DatasetConfig:
+# ==============================================================================
+train/utils.DatasetConfig.batch_size = %BATCH_SIZE
+train/utils.DatasetConfig.mixture_or_task_name = %MIXTURE_OR_TASK_NAME
+train/utils.DatasetConfig.module = %MIXTURE_OR_TASK_MODULE
+train/utils.DatasetConfig.pack = True
+train/utils.DatasetConfig.seed = None
+train/utils.DatasetConfig.shuffle = %SHUFFLE_TRAIN_EXAMPLES
+train/utils.DatasetConfig.split = 'train'
+train/utils.DatasetConfig.task_feature_lengths = %TASK_FEATURE_LENGTHS
+train/utils.DatasetConfig.use_cached = %USE_CACHED_TASKS
+
+# Parameters for train_eval/utils.DatasetConfig:
+# ==============================================================================
+train_eval/utils.DatasetConfig.batch_size = %BATCH_SIZE
+train_eval/utils.DatasetConfig.mixture_or_task_name = %MIXTURE_OR_TASK_NAME
+train_eval/utils.DatasetConfig.module = %MIXTURE_OR_TASK_MODULE
+train_eval/utils.DatasetConfig.pack = True
+train_eval/utils.DatasetConfig.seed = 42
+train_eval/utils.DatasetConfig.shuffle = False
+train_eval/utils.DatasetConfig.split = 'validation'
+train_eval/utils.DatasetConfig.task_feature_lengths = %TASK_FEATURE_LENGTHS
+train_eval/utils.DatasetConfig.use_cached = %USE_CACHED_TASKS
+
+# Parameters for models.EncoderDecoderModel:
+# ==============================================================================
+models.EncoderDecoderModel.input_vocabulary = %VOCABULARY
+models.EncoderDecoderModel.label_smoothing = %LABEL_SMOOTHING
+models.EncoderDecoderModel.loss_normalizing_factor = %LOSS_NORMALIZING_FACTOR
+models.EncoderDecoderModel.module = @network.Transformer()
+models.EncoderDecoderModel.optimizer_def = %OPTIMIZER
+models.EncoderDecoderModel.output_vocabulary = %VOCABULARY
+models.EncoderDecoderModel.z_loss = %Z_LOSS
+
+# Parameters for partitioning.PjitPartitioner:
+# ==============================================================================
+partitioning.PjitPartitioner.logical_axis_rules = \
+    @partitioning.standard_logical_axis_rules()
+partitioning.PjitPartitioner.model_parallel_submesh = None
+partitioning.PjitPartitioner.num_partitions = 1
+
+# Parameters for utils.RestoreCheckpointConfig:
+# ==============================================================================
+utils.RestoreCheckpointConfig.path = []
+
+# Parameters for utils.SaveCheckpointConfig:
+# ==============================================================================
+utils.SaveCheckpointConfig.dtype = 'float32'
+utils.SaveCheckpointConfig.keep = 10
+utils.SaveCheckpointConfig.period = 10000
+utils.SaveCheckpointConfig.save_dataset = False
+
+# Parameters for seqio.SentencePieceVocabulary:
+# ==============================================================================
+seqio.SentencePieceVocabulary.sentencepiece_model_file = 'spiece.model'
+
+# Parameters for network.T5Config:
+# ==============================================================================
+network.T5Config.dropout_rate = %DROPOUT_RATE
+network.T5Config.dtype = 'bfloat16'
+network.T5Config.emb_dim = 512
+network.T5Config.head_dim = 64
+network.T5Config.logits_via_embedding = False
+network.T5Config.mlp_activations = ('gelu', 'linear')
+network.T5Config.mlp_dim = 2048
+network.T5Config.num_decoder_layers = 16
+network.T5Config.num_encoder_layers = 16
+network.T5Config.num_heads = 8
+network.T5Config.vocab_size = 32128
+
+# Parameters for train_script.train:
+# ==============================================================================
+train_script.train.checkpoint_cfg = @utils.CheckpointConfig()
+train_script.train.eval_period = 10000
+train_script.train.eval_steps = 20
+train_script.train.infer_eval_dataset_cfg = None
+train_script.train.model = %MODEL
+train_script.train.model_dir = %MODEL_DIR
+train_script.train.partitioner = @partitioning.PjitPartitioner()
+train_script.train.random_seed = %RANDOM_SEED
+train_script.train.summarize_config_fn = @gin_utils.summarize_gin_config
+train_script.train.total_steps = %TRAIN_STEPS
+train_script.train.train_dataset_cfg = @train/utils.DatasetConfig()
+train_script.train.train_eval_dataset_cfg = @train_eval/utils.DatasetConfig()
+train_script.train.trainer_cls = @trainer.Trainer
+train_script.train.use_hardware_rng = %USE_HARDWARE_RNG
+
+# Parameters for trainer.Trainer:
+# ==============================================================================
+trainer.Trainer.learning_rate_fn = @utils.create_learning_rate_scheduler()
+trainer.Trainer.num_microbatches = None
+
+# Parameters for network.Transformer:
+# ==============================================================================
+network.Transformer.config = @network.T5Config()

small_nl16.gin

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+# T5.1.1 Efficient small nl16 model.
+
+import seqio
+include 't5x/examples/t5/t5_1_1/base.gin' # imports vocab, optimizer and model.
+
+# ------------------- Network specification overrides --------------------------
+network.Transformer.config = @network.T5Config()
+network.T5Config:
+  emb_dim = 512
+  num_heads = 8
+  num_encoder_layers = 16
+  num_decoder_layers = 16
+  head_dim = 64
+  mlp_dim = 2048
+
+# ------------------- Model specification overrides --------------------------
+VOCABULARY = @seqio.SentencePieceVocabulary()
+seqio.SentencePieceVocabulary.sentencepiece_model_file = "spiece.model"
+
+MODEL = @models.EncoderDecoderModel()
+models.EncoderDecoderModel:
+  input_vocabulary = %VOCABULARY
+  output_vocabulary = %VOCABULARY

small_nl16_pretrain.gin

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+# Register necessary SeqIO Tasks/Mixtures.
+from __gin__ import dynamic_registration
+from t5x import utils
+from t5x import partitioning
+import tasks
+import __main__ as train_script
+
+include 'small_nl16.gin'
+include 't5x/configs/runs/pretrain.gin'
+
+
+# ------------------- Training specification overrides --------------------------
+train_script.train:
+  eval_period = 10000
+
+utils.SaveCheckpointConfig:
+  period = 10000
+  keep = 10
+
+MIXTURE_OR_TASK_NAME = "pretrain_finnish_ul2"
+USE_CACHED_TASKS = False
+TASK_FEATURE_LENGTHS = {"inputs": 512, "targets": 512}
+TRAIN_STEPS = 500000
+DROPOUT_RATE = 0.0
+BATCH_SIZE = 256

spiece.model

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:b39375bd095c6d78f90949701049adc8f2a8fc1350c8c569c68ba079c80bda3f
+size 821929

start_train.sh

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+# set train hyperparams
+unset LD_PRELOAD
+
+PROJECT_DIR="/researchdisk/ul2-small-nl16-finnish"
+T5X_DIR=${HOME}"/t5x"  # directory where the t5x is cloned.
+MODEL_DIR="/researchdisk/ul2-small-nl16-finnish"
+export PYTHONPATH=${PROJECT_DIR}
+
+python3 ${T5X_DIR}/t5x/train.py \
+  --gin_search_paths=${PROJECT_DIR} \
+  --gin_file="small_nl16_pretrain.gin" \
+  --gin.MODEL_DIR=\"${MODEL_DIR}\"

tasks.py

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+import functools
+import seqio
+import tensorflow as tf
+import t5.data
+from datasets import load_dataset, load_from_disk
+from t5.data import postprocessors
+from t5.data import preprocessors
+from t5.evaluation import metrics
+from seqio import FunctionDataSource, utils
+
+from ul2_objective import ul2_objective
+
+# values from UL2 paper https://arxiv.org/pdf/2205.05131.pdf chapter 3.1.2 table 1
+R_DENOISER_SPAN_LENGTHS = [3.0, 8.0]
+X_DENOISER_SPAN_LENGTHS = [3.0, 8.0, 64.0, 64.0]
+R_DENOISER_CORRUPT_RATES = [0.15, 0.15]
+X_DENOISER_CORRUPT_RATES = [0.5, 0.5, 0.15, 0.5]
+
+R_DENOISER_TOKEN_PREFIX = '[NLU]'
+X_DENOISER_TOKEN_PREFIX = '[NLG]'
+S_DENOISER_TOKEN_PREFIX = '[S2S]'
+
+TaskRegistry = seqio.TaskRegistry
+
+vocabulary = seqio.SentencePieceVocabulary('spiece.model', extra_ids=0)
+
+DEFAULT_OUTPUT_FEATURES = {
+    "inputs": seqio.Feature(
+        vocabulary=vocabulary, add_eos=True,
+        required=False),
+    "targets": seqio.Feature(
+        vocabulary=vocabulary, add_eos=True)
+}
+
+
+def gen_dataset(split, shuffle=False, seed=None, column="text", dataset=None):
+    if shuffle:
+        if seed:
+            dataset = dataset.shuffle(seed=seed)
+        else:
+            dataset = dataset.shuffle()
+    while True:
+        for item in dataset[str(split)]:
+            if item[column] is not None:
+                yield item[column]
+
+
+def dataset_fn(split, shuffle_files, seed=None, dataset=None):
+    return tf.data.Dataset.from_generator(
+        functools.partial(gen_dataset, split, shuffle_files,
+                          seed, dataset=dataset),
+        output_signature=tf.TensorSpec(
+            shape=(), dtype=tf.string, name=dataset_name)
+    )
+
+
+@utils.map_over_dataset
+def target_to_key(x, key_map, target_key):
+    """Assign the value from the dataset to target_key in key_map"""
+    return {**key_map, target_key: x}
+
+
+dataset_name = "/researchdisk/lm_training_dataset_full"
+dataset_params = {"from_disk_path": dataset_name}
+
+if "from_disk_path" in dataset_params:
+    dataset = load_from_disk(dataset_params.get("from_disk_path"))
+else:
+    dataset = load_dataset(**dataset_params)
+
+dataset_shapes = {"train": dataset["train"].num_rows,
+                  "validation": dataset["validation"].num_rows}
+
+TaskRegistry.add(
+    "pretrain_finnish_ul2",
+    source=seqio.FunctionDataSource(
+        dataset_fn=functools.partial(dataset_fn, dataset=dataset),
+        splits=("train", "validation"),
+        caching_permitted=False,
+        num_input_examples=dataset_shapes,
+    ),
+    preprocessors=[
+        functools.partial(
+            target_to_key, key_map={
+                "inputs": None,
+                "targets": None,
+            }, target_key="targets"),
+        seqio.preprocessors.tokenize,
+        functools.partial(
+            ul2_objective,
+            shard_ds=False,
+            use_prefix_lm_task=True,  # use S-denoising
+            rates=[0.4 / len(R_DENOISER_SPAN_LENGTHS)]*len(R_DENOISER_SPAN_LENGTHS) + [
+                0.4 / len(X_DENOISER_SPAN_LENGTHS)]*len(X_DENOISER_SPAN_LENGTHS) + [0.2],  # equal total 40% rate for both R- and X-denoisers + 20% for S-denoising (suggested at the paper chapter 4.5)
+            mean_noise_span_lengths=R_DENOISER_SPAN_LENGTHS + X_DENOISER_SPAN_LENGTHS,
+            noise_densities=R_DENOISER_CORRUPT_RATES + X_DENOISER_CORRUPT_RATES,
+            optional_task_prefixes=[R_DENOISER_TOKEN_PREFIX]*len(R_DENOISER_SPAN_LENGTHS) + [
+                X_DENOISER_TOKEN_PREFIX]*len(X_DENOISER_SPAN_LENGTHS) + [S_DENOISER_TOKEN_PREFIX],
+            reserved_for_packing=1,  # make room for task prefix token
+        ),
+        seqio.preprocessors.append_eos_after_trim,
+    ],
+    output_features={"targets": DEFAULT_OUTPUT_FEATURES["targets"]},
+    metric_fns=[metrics.accuracy]
+)

train/events.out.tfevents.1665907259.t1v-n-12f94ad0-w-0.185363.0.v2

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:0c87efc6802f4bdc5c6ba5fd3d8e13c0856ef1ce5854183f4d07efa3a3489342
+size 5950

train_sentencepiece.py

@@ -0,0 +1,7 @@
+import sentencepiece as spm
+
+spm.SentencePieceTrainer.train(input="/researchdisk/training_dataset_sentences/train.txt", model_prefix='spiece', vocab_size=32000, character_coverage=1.0,
+                                pad_id=0, unk_id=2, eos_id=1, bos_id=-1,
+                                user_defined_symbols=['[NLU]', '[NLG]', '[S2S]'],
+                                train_extremely_large_corpus=True,
+                                num_threads=96, input_sentence_size=50000000, shuffle_input_sentence=True)

training_eval/pretrain_finnish_ul2/events.out.tfevents.1665907259.t1v-n-12f94ad0-w-0.185363.1.v2

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:cac17ca4282fe1cb0aafdd1122b0c6fda6d225a5fc62dbb60c311ee2f4c67d7b
+size 40

ul2_objective.py

@@ -0,0 +1,183 @@
+import functools
+import tensorflow as tf
+import seqio
+import t5.data
+from typing import Optional, Sequence
+
+# found this function and modified from https://github.com/GoogleCloudPlatform/t5x-on-vertex-ai/blob/main/tasks/custom_tasks.py#L78
+# UL2 paper appendix code missed this function
+def prepend_prompt(dataset: tf.data.Dataset,
+                   output_features: seqio.preprocessors.OutputFeaturesType,
+                   sequence_length: Optional[
+                       seqio.preprocessors.SequenceLengthType] = None,
+                   prompt_mode: str = "",
+                   key: str = "inputs",
+                   mode: str = "") -> tf.data.Dataset:
+    """Prepends a prompt at the beginning of an input sequence."""
+    del sequence_length
+    if prompt_mode and mode:
+        # output_features may not have inputs key
+        out_keys = list(output_features.keys())
+        prompt_tokens = output_features[out_keys[0]
+                                        ].vocabulary.encode_tf(prompt_mode)
+
+        def add_to_inputs(x):
+            x[key] = tf.concat([prompt_tokens, x[key]], axis=0)
+            return x
+
+        dataset = dataset.map(add_to_inputs)
+    return dataset
+
+# modified from t5.data.preprocessors because output_features may not have inputs key
+def split_tokens_to_inputs_length(dataset, sequence_length,
+                                  output_features, **kwargs):
+    max_tokens = sequence_length['inputs']
+    # output_features may not have inputs key
+    out_keys = list(output_features.keys())
+    if output_features[out_keys[0]].add_eos:
+        # Leave room to insert an EOS token.
+        max_tokens -= 1
+
+    return t5.data.preprocessors.split_tokens(dataset, max_tokens_per_segment=max_tokens, **kwargs)
+
+# modified from t5.data.preprocessors because output_features may not have inputs key
+def prefix_lm(dataset, sequence_length, output_features):
+    """Prefix language modeling objective used in Raffel et al. 2019."""
+    ds = dataset
+    ds = t5.data.preprocessors.select_random_chunk(ds, output_features=output_features,
+                                                   feature_key='targets', max_length=65536)
+    ds = split_tokens_to_inputs_length(ds, output_features=output_features,
+                                       sequence_length=sequence_length)
+    ds = t5.data.preprocessors.denoise(
+        ds,
+        output_features,
+        inputs_fn=t5.data.preprocessors.drop_nonnoise_tokens,
+        targets_fn=t5.data.preprocessors.drop_noise_tokens,
+        noise_density=0.5,
+        noise_mask_fn=t5.data.preprocessors.random_prefix_noise_mask,
+    )
+    return ds
+
+# copied from UL2 paper https://arxiv.org/pdf/2205.05131.pdf appendix chapter 9.2
+# note: modified to use the prefix_lm() from above instead of the default t5.data.preprocessors.prefix_lm() because output_features may not have inputs key
+def ul2_objective(dataset: tf.data.Dataset,
+                  sequence_length: seqio.preprocessors.SequenceLengthType,
+                  output_features: seqio.preprocessors.OutputFeaturesType,
+                  use_prefix_lm_task: bool = False,
+                  rates: Optional[Sequence[float]] = None,
+                  mean_noise_span_lengths: Sequence[float] = (3.0,),
+                  noise_densities: Sequence[float] = (0.15,),
+                  shard_ds: bool = True,
+                  optional_task_prefixes: Optional[Sequence[str]] = None,
+                  input_feature_key: str = "inputs",
+                  merge_examples_to_reduce_padding: bool = True,
+                  reserved_for_packing: bool = None,
+                  seed: int = 7) -> tf.data.Dataset:
+    """UL2-like pre-training objectives.
+    This preprocessor amounts to calling the 'span_corruption' function several
+    times with different values of 'noise_density' and 'mean_noise_span_length'.
+    We either shard or copy the dataset, then apply each function to each shard.
+    Add S-denoising (prefixLM) using use_prefix_lm_task.
+    Args:
+        dataset: A tf.data.Dataset with dictionaries containing the key 'input_feature_key'.
+        sequence_length: dict mapping of feature key to int length for that feature.
+        output_features: mapping of keys to features.
+        use_prefix_lm_task: <bool> If True, include PrefixLM in the task mix.
+        rates: <Optional<List<float>> List of rates per task. If None, tasks are sampled uniformly.
+        mean_noise_span_lengths: List of mean number of tokens per masked span per example.
+        noise_densities: List of what fraction of the tokens to mask.
+        shard_ds: <bool> If True, shard dataset per objective.
+        optional_task_prefixes: <Optional<list<str>> Strings to prepend for each corruption scheme. NOTE: If including prefixLM task, it must be the last prefix.
+        input_feature_key: which feature to use from the dataset as the input text tokens.
+        merge_examples_to_reduce_padding: if True, combines multiple input examples to reduce padding.
+        reserved_for_packing: if specified, reduces the desired inputs length by the specified amount to enable multiple examples to be packed together downstream.
+        seed: tf.int64 for controlling the random choice of spans.
+    Returns:
+        a dataset
+    """
+
+    if optional_task_prefixes:  # Ensure each task has a prefix.
+        num_tasks = len(noise_densities) + int(use_prefix_lm_task)
+        valid_number_of_prefixes = num_tasks == len(optional_task_prefixes)
+        if not valid_number_of_prefixes:
+            raise ValueError(
+                "Number of task prefixes must match number of tasks.")
+    inputs_length = sequence_length[input_feature_key]
+    input_lengths, targets_lengths = [], []
+    sequence_lengths = {x: y for x, y in sequence_length.items()}
+    if reserved_for_packing:
+        inputs_length -= reserved_for_packing
+        for x, y in sequence_length.items():
+            sequence_lengths[x] = y - reserved_for_packing
+    hyperparams = list(zip(mean_noise_span_lengths, noise_densities))
+    for mean_noise_span_length, noise_density in hyperparams:
+        input_length, targets_length = t5.data.preprocessors.random_spans_helper(
+            extra_tokens_per_span_inputs=1,
+            extra_tokens_per_span_targets=1,
+            inputs_length=inputs_length,
+            mean_noise_span_length=mean_noise_span_length,
+            noise_density=noise_density)
+        input_lengths.append(input_length)
+        targets_lengths.append(targets_length)
+
+        if sequence_length["targets"] < targets_length:
+            upper_bound = max(targets_lengths)
+            raise ValueError(
+                f'Expected max targets length for span corruption ({upper_bound}) is '
+                f'greater than configured targets length '
+                f"({sequence_length['targets']})")
+    ds = dataset
+    ds = t5.data.preprocessors.select_random_chunk(
+        ds,
+        output_features=output_features,
+        feature_key="targets",
+        max_length=65536)
+    if merge_examples_to_reduce_padding:
+        ds = t5.data.preprocessors.reduce_concat_tokens(
+            ds, feature_key="targets", batch_size=128)
+    num_shards = len(input_lengths) + int(use_prefix_lm_task)
+    if shard_ds:
+        ds_shards = [ds.shard(num_shards, i) for i in range(num_shards)]
+    else:
+        ds_shards = [ds for _ in range(num_shards)]
+    processed_ds = []
+    hyperparams = zip(input_lengths, hyperparams, range(num_shards))
+    for input_length, (noise_span_length, noise_density), i in hyperparams:
+        ds = ds_shards[i]
+        ds = t5.data.preprocessors.split_tokens(
+            ds,
+            feature_key="targets",
+            min_tokens_per_segment=None,
+            max_tokens_per_segment=input_length)
+        ds = t5.data.preprocessors.denoise(
+            ds,
+            output_features,
+            inputs_fn=t5.data.preprocessors.noise_span_to_unique_sentinel,
+            targets_fn=t5.data.preprocessors.nonnoise_span_to_unique_sentinel,
+            noise_density=noise_density,
+            noise_mask_fn=functools.partial(
+                t5.data.preprocessors.random_spans_noise_mask,
+                mean_noise_span_length=noise_span_length),
+            input_feature_key=input_feature_key)
+        if optional_task_prefixes:
+            ds = prepend_prompt(
+                ds,
+                output_features,
+                prompt_mode=optional_task_prefixes[i],
+                mode=optional_task_prefixes[i],
+                key=input_feature_key)
+        processed_ds.append(ds)
+    if use_prefix_lm_task:
+        ds = ds_shards[-1]
+        ds = prefix_lm(
+            ds, sequence_lengths, output_features)
+        if optional_task_prefixes:
+            ds = prepend_prompt(
+                ds,
+                output_features,
+                prompt_mode=optional_task_prefixes[-1],
+                mode=optional_task_prefixes[-1],
+                key=input_feature_key)
+        processed_ds.append(ds)
+    ds = tf.data.experimental.sample_from_datasets(processed_ds, rates, seed)
+    return ds