System Info

🤗 Diffusers version: 0.33.0.dev0
    Platform: Linux-6.8.0-55-generic-x86_64-with-glibc2.39
    Running on Google Colab?: No
    Python version: 3.10.11
    PyTorch version (GPU?): 2.7.1+cu126 (True)
    Flax version (CPU?/GPU?/TPU?): not installed (NA)
    Jax version: not installed
    JaxLib version: not installed
    Huggingface_hub version: 0.30.1
    Transformers version: 4.52.4
    Accelerate version: 1.8.1
    PEFT version: 0.15.2
    Bitsandbytes version: 0.45.4
    Safetensors version: 0.5.3
    xFormers version: 0.0.27.post2
    Accelerator: NVIDIA GeForce RTX 3090, 24576 MiB
    Using GPU in script?:
    Using distributed or parallel set-up in script?:

Information

• The official example scripts
• My own modified scripts

Tasks

• One of the scripts in the examples/ folder of Accelerate or an officially supported no_trainer script in the examples folder of the transformers repo (such as run_no_trainer_glue.py)
• My own task or dataset (give details below)

Reproduction

1. set the follow argument in "train_dreambooth.py" or other similar demos such as "train_amused.py":
   parser.add_argument( "--validation_prompt", type=str, default=["A photo of sks dog in a bucket", "A sks cat wearing a coat"], nargs="*", help="A prompt that is used during validation to verify that the model is learning.", )
2. An error occured at if accelerator.is_main_process: tracker_name = "dreambooth-lora" accelerator.init_trackers(tracker_name, config=vars(args)) with
   "ValueError: value should be one of int, float, str, bool, or torch.Tensor"

Expected behavior

I set multiple prompts with nargs for argument "--validation_prompt " in "train_dreambooth.py":

parser.add_argument( "--validation_prompt", type=str, default=["A photo of sks dog in a bucket", "A sks cat wearing a coat"], nargs="*", help="A prompt that is used during validation to verify that the model is learning.", )
but an error occured at if accelerator.is_main_process: tracker_name = "dreambooth-lora" accelerator.init_trackers(tracker_name, config=vars(args))
with "ValueError: value should be one of int, float, str, bool, or torch.Tensor".
Is it because tensorboard only support basic Python types and PyTorch tensors but not a custom object such as list?