The following values were not passed to `accelerate launch` and had defaults used instead:
    `--num_processes` was set to a value of `1`
    `--num_machines` was set to a value of `1`
    `--mixed_precision` was set to a value of `'no'`
    `--num_cpu_threads_per_process` was set to `1` to improve out-of-box performance
To avoid this warning pass in values for each of the problematic parameters or run `accelerate config`.
Generating class images:   0% 0/50 [00:06<?, ?it/s]
Traceback (most recent call last):
  File "/content/diffusers/examples/dreambooth/train_dreambooth.py", line 606, in <module>
    main()
  File "/content/diffusers/examples/dreambooth/train_dreambooth.py", line 362, in main
    images = pipeline(example["prompt"]).images
  File "/usr/local/lib/python3.7/dist-packages/torch/autograd/grad_mode.py", line 27, in decorate_context
    return func(*args, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/diffusers/pipelines/stable_diffusion/pipeline_stable_diffusion.py", line 259, in __call__
    noise_pred = self.unet(latent_model_input, t, encoder_hidden_states=text_embeddings).sample
  File "/usr/local/lib/python3.7/dist-packages/torch/nn/modules/module.py", line 1130, in _call_impl
    return forward_call(*input, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/diffusers/models/unet_2d_condition.py", line 254, in forward
    encoder_hidden_states=encoder_hidden_states,
  File "/usr/local/lib/python3.7/dist-packages/torch/nn/modules/module.py", line 1130, in _call_impl
    return forward_call(*input, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/diffusers/models/unet_blocks.py", line 565, in forward
    hidden_states = attn(hidden_states, context=encoder_hidden_states)
  File "/usr/local/lib/python3.7/dist-packages/torch/nn/modules/module.py", line 1130, in _call_impl
    return forward_call(*input, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/diffusers/models/attention.py", line 167, in forward
    hidden_states = block(hidden_states, context=context)
  File "/usr/local/lib/python3.7/dist-packages/torch/nn/modules/module.py", line 1130, in _call_impl
    return forward_call(*input, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/diffusers/models/attention.py", line 217, in forward
    hidden_states = self.attn1(self.norm1(hidden_states)) + hidden_states
  File "/usr/local/lib/python3.7/dist-packages/torch/nn/modules/module.py", line 1130, in _call_impl
    return forward_call(*input, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/diffusers/models/attention.py", line 287, in forward
    out = xformers.ops.memory_efficient_attention(q, k, v, attn_bias=None, op=self.attention_op)
  File "/usr/local/lib/python3.7/dist-packages/xformers/ops.py", line 657, in memory_efficient_attention
    query=query, key=key, value=value, attn_bias=attn_bias, p=p
  File "/usr/local/lib/python3.7/dist-packages/xformers/ops.py", line 261, in forward_no_grad
    causal=isinstance(attn_bias, LowerTriangularMask),
  File "/usr/local/lib/python3.7/dist-packages/xformers/ops.py", line 46, in no_such_operator
    f"No such operator xformers::{name} - did you forget to build xformers with `python setup.py develop`?"
RuntimeError: No such operator xformers::efficient_attention_forward_cutlass - did you forget to build xformers with `python setup.py develop`?
Traceback (most recent call last):
  File "/usr/local/bin/accelerate", line 8, in <module>
    sys.exit(main())
  File "/usr/local/lib/python3.7/dist-packages/accelerate/commands/accelerate_cli.py", line 43, in main
    args.func(args)
  File "/usr/local/lib/python3.7/dist-packages/accelerate/commands/launch.py", line 837, in launch_command
    simple_launcher(args)
  File "/usr/local/lib/python3.7/dist-packages/accelerate/commands/launch.py", line 354, in simple_launcher
    raise subprocess.CalledProcessError(returncode=process.returncode, cmd=cmd)
subprocess.CalledProcessError: Command '['/usr/bin/python3', '/content/diffusers/examples/dreambooth/train_dreambooth.py', '--pretrained_model_name_or_path=/content/gdrive/MyDrive/stable-diffusion-v1-4', '--instance_data_dir=/content/data/ViajeroFree', '--class_data_dir=/content/data/GabrielBear', '--output_dir=/content/models/ViajeroFree', '--with_prior_preservation', '--prior_loss_weight=1.0', '--instance_prompt=instance_prompt', '--class_prompt=class_prompt', '--resolution=512', '--train_batch_size=1', '--gradient_accumulation_steps=1', '--use_8bit_adam', '--learning_rate=5e-6', '--lr_scheduler=constant', '--lr_warmup_steps=0', '--num_class_images=200', '--max_train_steps=800']' returned non-zero exit status 1.