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import argparse
import itertools
import math
import os
import datetime
from pathlib import Path

import numpy as np
import torch
import torch.nn.functional as F
import torch.utils.checkpoint

from accelerate import Accelerator
from accelerate.logging import get_logger
from accelerate.utils import LoggerType, set_seed
from diffusers import AutoencoderKL, DDPMScheduler, PNDMScheduler, LMSDiscreteScheduler, StableDiffusionPipeline, UNet2DConditionModel
from diffusers.optimization import get_scheduler
from pipelines.stable_diffusion.no_check import NoCheck
from PIL import Image
from tqdm.auto import tqdm
from transformers import CLIPFeatureExtractor, CLIPTextModel, CLIPTokenizer
from slugify import slugify
import json
import os

from data.dreambooth.csv import CSVDataModule
from data.dreambooth.prompt import PromptDataset

logger = get_logger(__name__)


def parse_args():
    parser = argparse.ArgumentParser(
        description="Simple example of a training script."
    )
    parser.add_argument(
        "--pretrained_model_name_or_path",
        type=str,
        default=None,
        help="Path to pretrained model or model identifier from huggingface.co/models.",
    )
    parser.add_argument(
        "--tokenizer_name",
        type=str,
        default=None,
        help="Pretrained tokenizer name or path if not the same as model_name",
    )
    parser.add_argument(
        "--train_data_file",
        type=str,
        default=None,
        help="A folder containing the training data."
    )
    parser.add_argument(
        "--identifier",
        type=str,
        default=None,
        help="A token to use as a placeholder for the concept.",
    )
    parser.add_argument(
        "--repeats",
        type=int,
        default=100,
        help="How many times to repeat the training data.")
    parser.add_argument(
        "--output_dir",
        type=str,
        default="dreambooth-model",
        help="The output directory where the model predictions and checkpoints will be written.",
    )
    parser.add_argument(
        "--seed",
        type=int,
        default=None,
        help="A seed for reproducible training.")
    parser.add_argument(
        "--resolution",
        type=int,
        default=512,
        help=(
            "The resolution for input images, all the images in the train/validation dataset will be resized to this"
            " resolution"
        ),
    )
    parser.add_argument(
        "--center_crop",
        action="store_true",
        help="Whether to center crop images before resizing to resolution"
    )
    parser.add_argument(
        "--num_train_epochs",
        type=int,
        default=100)
    parser.add_argument(
        "--max_train_steps",
        type=int,
        default=5000,
        help="Total number of training steps to perform.  If provided, overrides num_train_epochs.",
    )
    parser.add_argument(
        "--gradient_accumulation_steps",
        type=int,
        default=1,
        help="Number of updates steps to accumulate before performing a backward/update pass.",
    )
    parser.add_argument(
        "--gradient_checkpointing",
        action="store_true",
        help="Whether or not to use gradient checkpointing to save memory at the expense of slower backward pass.",
    )
    parser.add_argument(
        "--learning_rate",
        type=float,
        default=5e-6,
        help="Initial learning rate (after the potential warmup period) to use.",
    )
    parser.add_argument(
        "--scale_lr",
        action="store_true",
        default=True,
        help="Scale the learning rate by the number of GPUs, gradient accumulation steps, and batch size.",
    )
    parser.add_argument(
        "--lr_scheduler",
        type=str,
        default="constant",
        help=(
            'The scheduler type to use. Choose between ["linear", "cosine", "cosine_with_restarts", "polynomial",'
            ' "constant", "constant_with_warmup"]'
        ),
    )
    parser.add_argument(
        "--lr_warmup_steps",
        type=int,
        default=0,
        help="Number of steps for the warmup in the lr scheduler."
    )
    parser.add_argument(
        "--adam_beta1",
        type=float,
        default=0.9,
        help="The beta1 parameter for the Adam optimizer."
    )
    parser.add_argument(
        "--adam_beta2",
        type=float,
        default=0.999,
        help="The beta2 parameter for the Adam optimizer."
    )
    parser.add_argument(
        "--adam_weight_decay",
        type=float,
        default=1e-2,
        help="Weight decay to use."
    )
    parser.add_argument(
        "--adam_epsilon",
        type=float,
        default=1e-08,
        help="Epsilon value for the Adam optimizer"
    )
    parser.add_argument(
        "--mixed_precision",
        type=str,
        default="no",
        choices=["no", "fp16", "bf16"],
        help=(
            "Whether to use mixed precision. Choose"
            "between fp16 and bf16 (bfloat16). Bf16 requires PyTorch >= 1.10."
            "and an Nvidia Ampere GPU."
        ),
    )
    parser.add_argument(
        "--local_rank",
        type=int,
        default=-1,
        help="For distributed training: local_rank"
    )
    parser.add_argument(
        "--checkpoint_frequency",
        type=int,
        default=500,
        help="How often to save a checkpoint and sample image",
    )
    parser.add_argument(
        "--sample_image_size",
        type=int,
        default=512,
        help="Size of sample images",
    )
    parser.add_argument(
        "--stable_sample_batches",
        type=int,
        default=1,
        help="Number of fixed seed sample batches to generate per checkpoint",
    )
    parser.add_argument(
        "--random_sample_batches",
        type=int,
        default=1,
        help="Number of random seed sample batches to generate per checkpoint",
    )
    parser.add_argument(
        "--sample_batch_size",
        type=int,
        default=1,
        help="Number of samples to generate per batch",
    )
    parser.add_argument(
        "--train_batch_size",
        type=int,
        default=1,
        help="Batch size (per device) for the training dataloader."
    )
    parser.add_argument(
        "--sample_steps",
        type=int,
        default=50,
        help="Number of steps for sample generation. Higher values will result in more detailed samples, but longer runtimes.",
    )
    parser.add_argument(
        "--instance_prompt",
        type=str,
        default=None,
        help="The prompt with identifier specifing the instance",
    )
    parser.add_argument(
        "--class_data_dir",
        type=str,
        default=None,
        required=False,
        help="A folder containing the training data of class images.",
    )
    parser.add_argument(
        "--class_prompt",
        type=str,
        default=None,
        help="The prompt to specify images in the same class as provided intance images.",
    )
    parser.add_argument(
        "--with_prior_preservation",
        default=False,
        action="store_true",
        help="Flag to add prior perservation loss.",
    )
    parser.add_argument(
        "--num_class_images",
        type=int,
        default=100,
        help=(
            "Minimal class images for prior perversation loss. If not have enough images, additional images will be"
            " sampled with class_prompt."
        ),
    )
    parser.add_argument(
        "--config",
        type=str,
        default=None,
        help="Path to a JSON configuration file containing arguments for invoking this script."
    )

    args = parser.parse_args()
    if args.config is not None:
        with open(args.config, 'rt') as f:
            args = parser.parse_args(
                namespace=argparse.Namespace(**json.load(f)["args"]))

    env_local_rank = int(os.environ.get("LOCAL_RANK", -1))
    if env_local_rank != -1 and env_local_rank != args.local_rank:
        args.local_rank = env_local_rank

    if args.train_data_file is None:
        raise ValueError("You must specify --train_data_file")

    if args.pretrained_model_name_or_path is None:
        raise ValueError("You must specify --pretrained_model_name_or_path")

    if args.instance_prompt is None:
        raise ValueError("You must specify --instance_prompt")

    if args.identifier is None:
        raise ValueError("You must specify --identifier")

    if args.output_dir is None:
        raise ValueError("You must specify --output_dir")

    if args.with_prior_preservation:
        if args.class_data_dir is None:
            raise ValueError("You must specify --class_data_dir")
        if args.class_prompt is None:
            raise ValueError("You must specify --class_prompt")

    return args


def freeze_params(params):
    for param in params:
        param.requires_grad = False


def make_grid(images, rows, cols):
    w, h = images[0].size
    grid = Image.new('RGB', size=(cols*w, rows*h))
    for i, image in enumerate(images):
        grid.paste(image, box=(i % cols*w, i//cols*h))
    return grid


class Checkpointer:
    def __init__(
        self,
        datamodule,
        accelerator,
        vae,
        unet,
        tokenizer,
        text_encoder,
        output_dir,
        sample_image_size,
        random_sample_batches,
        sample_batch_size,
        stable_sample_batches,
        seed
    ):
        self.datamodule = datamodule
        self.accelerator = accelerator
        self.vae = vae
        self.unet = unet
        self.tokenizer = tokenizer
        self.text_encoder = text_encoder
        self.output_dir = output_dir
        self.sample_image_size = sample_image_size
        self.seed = seed
        self.random_sample_batches = random_sample_batches
        self.sample_batch_size = sample_batch_size
        self.stable_sample_batches = stable_sample_batches

    @torch.no_grad()
    def checkpoint(self):
        print("Saving model...")

        unwrapped = self.accelerator.unwrap_model(self.unet)
        pipeline = StableDiffusionPipeline(
            text_encoder=self.text_encoder,
            vae=self.vae,
            unet=self.accelerator.unwrap_model(self.unet),
            tokenizer=self.tokenizer,
            scheduler=PNDMScheduler(
                beta_start=0.00085, beta_end=0.012, beta_schedule="scaled_linear", skip_prk_steps=True
            ),
            safety_checker=NoCheck(),
            feature_extractor=CLIPFeatureExtractor.from_pretrained("openai/clip-vit-base-patch32"),
        )
        pipeline.enable_attention_slicing()
        pipeline.save_pretrained(f"{self.output_dir}/model")

        del unwrapped
        del pipeline

        if torch.cuda.is_available():
            torch.cuda.empty_cache()

    @torch.no_grad()
    def save_samples(self, mode, step, height, width, guidance_scale, eta, num_inference_steps):
        samples_path = f"{self.output_dir}/samples/{mode}"
        os.makedirs(samples_path, exist_ok=True)
        checker = NoCheck()

        unwrapped = self.accelerator.unwrap_model(self.unet)
        pipeline = StableDiffusionPipeline(
            text_encoder=self.text_encoder,
            vae=self.vae,
            unet=unwrapped,
            tokenizer=self.tokenizer,
            scheduler=LMSDiscreteScheduler(
                beta_start=0.00085, beta_end=0.012, beta_schedule="scaled_linear"
            ),
            safety_checker=NoCheck(),
            feature_extractor=CLIPFeatureExtractor.from_pretrained("openai/clip-vit-base-patch32"),
        ).to(self.accelerator.device)
        pipeline.enable_attention_slicing()

        data = {
            "training": self.datamodule.train_dataloader(),
            "validation": self.datamodule.val_dataloader(),
        }[mode]

        if mode == "validation" and self.stable_sample_batches > 0 and step > 0:
            stable_latents = torch.randn(
                (self.sample_batch_size, pipeline.unet.in_channels, height // 8, width // 8),
                device=pipeline.device,
                generator=torch.Generator(device=pipeline.device).manual_seed(self.seed),
            )

            all_samples = []
            filename = f"stable_step_%d.png" % (step)

            data_enum = enumerate(data)

            # Generate and save stable samples
            for i in range(0, self.stable_sample_batches):
                prompt = [prompt for i, batch in data_enum for j, prompt in enumerate(
                    batch["prompts"]) if i * data.batch_size + j < self.sample_batch_size]

                with self.accelerator.autocast():
                    samples = pipeline(
                        prompt=prompt,
                        height=self.sample_image_size,
                        latents=stable_latents[:len(prompt)],
                        width=self.sample_image_size,
                        guidance_scale=guidance_scale,
                        eta=eta,
                        num_inference_steps=num_inference_steps,
                        output_type='pil'
                    )["sample"]

                all_samples += samples
                del samples

            image_grid = make_grid(all_samples, self.stable_sample_batches, self.sample_batch_size)
            image_grid.save(f"{samples_path}/{filename}")

            del all_samples
            del image_grid
            del stable_latents

        all_samples = []
        filename = f"step_%d.png" % (step)

        data_enum = enumerate(data)

        # Generate and save random samples
        for i in range(0, self.random_sample_batches):
            prompt = [prompt for i, batch in data_enum for j, prompt in enumerate(
                batch["prompts"]) if i * data.batch_size + j < self.sample_batch_size]

            with self.accelerator.autocast():
                samples = pipeline(
                    prompt=prompt,
                    height=self.sample_image_size,
                    width=self.sample_image_size,
                    guidance_scale=guidance_scale,
                    eta=eta,
                    num_inference_steps=num_inference_steps,
                    output_type='pil'
                )["sample"]

            all_samples += samples
            del samples

        image_grid = make_grid(all_samples, self.random_sample_batches, self.sample_batch_size)
        image_grid.save(f"{samples_path}/{filename}")

        del all_samples
        del image_grid

        del checker
        del unwrapped
        del pipeline

        if torch.cuda.is_available():
            torch.cuda.empty_cache()


def main():
    args = parse_args()

    now = datetime.datetime.now().strftime("%Y-%m-%dT%H-%M-%S")
    basepath = f"{args.output_dir}/{slugify(args.identifier)}/{now}"
    os.makedirs(basepath, exist_ok=True)

    accelerator = Accelerator(
        log_with=LoggerType.TENSORBOARD,
        logging_dir=f"{basepath}",
        gradient_accumulation_steps=args.gradient_accumulation_steps,
        mixed_precision=args.mixed_precision
    )

    # If passed along, set the training seed now.
    if args.seed is not None:
        set_seed(args.seed)

    if args.with_prior_preservation:
        class_images_dir = Path(args.class_data_dir)
        if not class_images_dir.exists():
            class_images_dir.mkdir(parents=True)
        cur_class_images = len(list(class_images_dir.iterdir()))

        if cur_class_images < args.num_class_images:
            torch_dtype = torch.float16 if accelerator.device.type == "cuda" else torch.float32
            pipeline = StableDiffusionPipeline.from_pretrained(
                args.pretrained_model_name_or_path, torch_dtype=torch_dtype)
            pipeline.set_progress_bar_config(disable=True)

            num_new_images = args.num_class_images - cur_class_images
            logger.info(f"Number of class images to sample: {num_new_images}.")

            sample_dataset = PromptDataset(args.class_prompt, num_new_images)
            sample_dataloader = torch.utils.data.DataLoader(sample_dataset, batch_size=args.sample_batch_size)

            sample_dataloader = accelerator.prepare(sample_dataloader)
            pipeline.to(accelerator.device)

            for example in tqdm(
                sample_dataloader, desc="Generating class images", disable=not accelerator.is_local_main_process
            ):
                with accelerator.autocast():
                    images = pipeline(example["prompt"]).images

                for i, image in enumerate(images):
                    image.save(class_images_dir / f"{example['index'][i] + cur_class_images}.jpg")

            del pipeline

            if torch.cuda.is_available():
                torch.cuda.empty_cache()

    # Load the tokenizer and add the placeholder token as a additional special token
    if args.tokenizer_name:
        tokenizer = CLIPTokenizer.from_pretrained(args.tokenizer_name)
    elif args.pretrained_model_name_or_path:
        tokenizer = CLIPTokenizer.from_pretrained(
            args.pretrained_model_name_or_path + '/tokenizer'
        )

    # Load models and create wrapper for stable diffusion
    text_encoder = CLIPTextModel.from_pretrained(
        args.pretrained_model_name_or_path + '/text_encoder',
    )
    vae = AutoencoderKL.from_pretrained(
        args.pretrained_model_name_or_path + '/vae',
    )
    unet = UNet2DConditionModel.from_pretrained(
        args.pretrained_model_name_or_path + '/unet',
    )

    if args.gradient_checkpointing:
        unet.enable_gradient_checkpointing()

    # slice_size = unet.config.attention_head_dim // 2
    # unet.set_attention_slice(slice_size)

    # Freeze text_encoder and vae
    freeze_params(vae.parameters())
    freeze_params(text_encoder.parameters())

    if args.scale_lr:
        args.learning_rate = (
            args.learning_rate * args.gradient_accumulation_steps *
            args.train_batch_size * accelerator.num_processes
        )

    # Initialize the optimizer
    optimizer = torch.optim.AdamW(
        unet.parameters(),  # only optimize unet
        lr=args.learning_rate,
        betas=(args.adam_beta1, args.adam_beta2),
        weight_decay=args.adam_weight_decay,
        eps=args.adam_epsilon,
    )

    # TODO (patil-suraj): laod scheduler using args
    noise_scheduler = DDPMScheduler(
        beta_start=0.00085, beta_end=0.012, beta_schedule="scaled_linear", num_train_timesteps=1000, tensor_format="pt"
    )

    def collate_fn(examples):
        prompts = [example["prompts"] for example in examples]
        input_ids = [example["instance_prompt_ids"] for example in examples]
        pixel_values = [example["instance_images"] for example in examples]

        # concat class and instance examples for prior preservation
        if args.with_prior_preservation:
            input_ids += [example["class_prompt_ids"] for example in examples]
            pixel_values += [example["class_images"] for example in examples]

        pixel_values = torch.stack(pixel_values)
        pixel_values = pixel_values.to(memory_format=torch.contiguous_format).float()

        input_ids = tokenizer.pad({"input_ids": input_ids}, padding=True, return_tensors="pt").input_ids

        batch = {
            "prompts": prompts,
            "input_ids": input_ids,
            "pixel_values": pixel_values,
        }
        return batch

    datamodule = CSVDataModule(
        data_file=args.train_data_file,
        batch_size=args.train_batch_size,
        tokenizer=tokenizer,
        instance_prompt=args.instance_prompt,
        class_data_root=args.class_data_dir if args.with_prior_preservation else None,
        class_prompt=args.class_prompt,
        size=args.resolution,
        identifier=args.identifier,
        repeats=args.repeats,
        center_crop=args.center_crop,
        collate_fn=collate_fn)

    datamodule.prepare_data()
    datamodule.setup()

    train_dataloader = datamodule.train_dataloader()
    val_dataloader = datamodule.val_dataloader()

    checkpointer = Checkpointer(
        datamodule=datamodule,
        accelerator=accelerator,
        vae=vae,
        unet=unet,
        tokenizer=tokenizer,
        text_encoder=text_encoder,
        output_dir=basepath,
        sample_image_size=args.sample_image_size,
        sample_batch_size=args.sample_batch_size,
        random_sample_batches=args.random_sample_batches,
        stable_sample_batches=args.stable_sample_batches,
        seed=args.seed
    )

    # Scheduler and math around the number of training steps.
    overrode_max_train_steps = False
    num_update_steps_per_epoch = math.ceil(
        (len(train_dataloader) + len(val_dataloader)) / args.gradient_accumulation_steps)
    if args.max_train_steps is None:
        args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch
        overrode_max_train_steps = True

    lr_scheduler = get_scheduler(
        args.lr_scheduler,
        optimizer=optimizer,
        num_warmup_steps=args.lr_warmup_steps * args.gradient_accumulation_steps,
        num_training_steps=args.max_train_steps * args.gradient_accumulation_steps,
    )

    unet, optimizer, train_dataloader, val_dataloader, lr_scheduler = accelerator.prepare(
        unet, optimizer, train_dataloader, val_dataloader, lr_scheduler
    )

    # Move vae and unet to device
    text_encoder.to(accelerator.device)
    vae.to(accelerator.device)

    # Keep text_encoder and vae in eval mode as we don't train these
    text_encoder.eval()
    vae.eval()

    # We need to recalculate our total training steps as the size of the training dataloader may have changed.
    num_update_steps_per_epoch = math.ceil(
        (len(train_dataloader) + len(val_dataloader)) / args.gradient_accumulation_steps)
    if overrode_max_train_steps:
        args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch
    # Afterwards we recalculate our number of training epochs
    args.num_train_epochs = math.ceil(
        args.max_train_steps / num_update_steps_per_epoch)

    # We need to initialize the trackers we use, and also store our configuration.
    # The trackers initializes automatically on the main process.
    if accelerator.is_main_process:
        accelerator.init_trackers("dreambooth", config=vars(args))

    # Train!
    total_batch_size = args.train_batch_size * accelerator.num_processes * args.gradient_accumulation_steps

    logger.info("***** Running training *****")
    logger.info(f"  Num Epochs = {args.num_train_epochs}")
    logger.info(f"  Instantaneous batch size per device = {args.train_batch_size}")
    logger.info(f"  Total train batch size (w. parallel, distributed & accumulation) = {total_batch_size}")
    logger.info(f"  Gradient Accumulation steps = {args.gradient_accumulation_steps}")
    logger.info(f"  Total optimization steps = {args.max_train_steps}")
    # Only show the progress bar once on each machine.

    global_step = 0
    min_val_loss = np.inf

    checkpointer.save_samples(
        "validation",
        0,
        args.resolution, args.resolution, 7.5, 0.0, args.sample_steps)

    local_progress_bar = tqdm(range(num_update_steps_per_epoch), disable=not accelerator.is_local_main_process)
    local_progress_bar.set_description("Steps")

    progress_bar = tqdm(range(args.max_train_steps), disable=not accelerator.is_local_main_process)
    progress_bar.set_description("Global steps")

    try:
        for epoch in range(args.num_train_epochs):
            local_progress_bar.reset()

            unet.train()
            train_loss = 0.0

            for step, batch in enumerate(train_dataloader):
                with accelerator.accumulate(unet):
                    with accelerator.autocast():
                        # Convert images to latent space
                        with torch.no_grad():
                            latents = vae.encode(batch["pixel_values"]).latent_dist.sample()
                            latents = latents * 0.18215

                        # Sample noise that we'll add to the latents
                        noise = torch.randn(latents.shape).to(latents.device)
                        bsz = latents.shape[0]
                        # Sample a random timestep for each image
                        timesteps = torch.randint(0, noise_scheduler.num_train_timesteps,
                                                  (bsz,), device=latents.device).long()

                        # Add noise to the latents according to the noise magnitude at each timestep
                        # (this is the forward diffusion process)
                        noisy_latents = noise_scheduler.add_noise(latents, noise, timesteps)

                        # Get the text embedding for conditioning
                        with torch.no_grad():
                            encoder_hidden_states = text_encoder(batch["input_ids"])[0]

                        # Predict the noise residual
                        noise_pred = unet(noisy_latents, timesteps, encoder_hidden_states).sample

                        loss = F.mse_loss(noise_pred, noise, reduction="none").mean([1, 2, 3]).mean()

                    accelerator.backward(loss)

                    optimizer.step()
                    if not accelerator.optimizer_step_was_skipped:
                        lr_scheduler.step()
                    optimizer.zero_grad(set_to_none=True)

                    loss = loss.detach().item()
                    train_loss += loss

                # Checks if the accelerator has performed an optimization step behind the scenes
                if accelerator.sync_gradients:
                    local_progress_bar.update(1)
                    progress_bar.update(1)

                    global_step += 1

                    if global_step % args.checkpoint_frequency == 0 and global_step > 0 and accelerator.is_main_process:
                        local_progress_bar.clear()
                        progress_bar.clear()

                        checkpointer.save_samples(
                            "training",
                            global_step,
                            args.resolution, args.resolution, 7.5, 0.0, args.sample_steps)

                logs = {"mode": "training", "loss": loss, "lr": lr_scheduler.get_last_lr()[0]}
                local_progress_bar.set_postfix(**logs)

                if global_step >= args.max_train_steps:
                    break

            train_loss /= len(train_dataloader)

            unet.eval()
            val_loss = 0.0

            for step, batch in enumerate(val_dataloader):
                with torch.no_grad(), accelerator.autocast():
                    latents = vae.encode(batch["pixel_values"]).latent_dist.sample()
                    latents = latents * 0.18215

                    noise = torch.randn(latents.shape).to(latents.device)
                    bsz = latents.shape[0]
                    timesteps = torch.randint(0, noise_scheduler.num_train_timesteps,
                                              (bsz,), device=latents.device).long()

                    noisy_latents = noise_scheduler.add_noise(latents, noise, timesteps)

                    encoder_hidden_states = text_encoder(batch["input_ids"])[0]

                    noise_pred = unet(noisy_latents, timesteps, encoder_hidden_states).sample

                    noise_pred, noise = accelerator.gather_for_metrics((noise_pred, noise))

                    loss = F.mse_loss(noise_pred, noise, reduction="none").mean([1, 2, 3]).mean()

                    loss = loss.detach().item()
                    val_loss += loss

                if accelerator.sync_gradients:
                    local_progress_bar.update(1)
                    progress_bar.update(1)

                logs = {"mode": "validation", "loss": loss}
                local_progress_bar.set_postfix(**logs)

            val_loss /= len(val_dataloader)

            accelerator.log({"train/loss": train_loss, "val/loss": val_loss}, step=global_step)

            local_progress_bar.clear()
            progress_bar.clear()

            if min_val_loss > val_loss:
                accelerator.print(f"Validation loss reached new minimum: {min_val_loss:.2e} -> {val_loss:.2e}")
                min_val_loss = val_loss

            checkpointer.save_samples(
                "validation",
                global_step,
                args.resolution, args.resolution, 7.5, 0.0, args.sample_steps)

            accelerator.wait_for_everyone()

        # Create the pipeline using using the trained modules and save it.
        if accelerator.is_main_process:
            print("Finished! Saving final checkpoint and resume state.")
            checkpointer.checkpoint()

            accelerator.end_training()

    except KeyboardInterrupt:
        if accelerator.is_main_process:
            print("Interrupted, saving checkpoint and resume state...")
            checkpointer.checkpoint()
            accelerator.end_training()
        quit()


if __name__ == "__main__":
    main()