docstr: Test whether trying to cast (or assigning a device to) a model after converting it in 8-bit will throw an error.
  Checks also if other models are casted correctly.
docstr_tok: ["Test","whether","trying","to","cast","(","or","assigning","a","device","to",")","a","model","after","converting","it","in","8-bit","will","throw","an","error",".","Checks","also","if","other","models","are","casted","correctly","."]
code: def test_device_and_dtype_assignment(self):
      r"""
      Test whether trying to cast (or assigning a device to) a model after converting it in 8-bit will throw an error.
      Checks also if other models are casted correctly.
      """
      with self.assertRaises(ValueError):
          # Tries with `str`
          self.model_4bit.to("cpu")
  
      with self.assertRaises(ValueError):
          # Tries with a `dtype``
          self.model_4bit.to(torch.float16)
  
      with self.assertRaises(ValueError):
          # Tries with a `device`
          self.model_4bit.to(torch.device("cuda:0"))
  
      with self.assertRaises(ValueError):
          # Tries with a `device`
          self.model_4bit.float()
  
      with self.assertRaises(ValueError):
          # Tries with a `device`
          self.model_4bit.half()
  
      # Test if we did not break anything
      encoded_input = self.tokenizer(
          self.input_text, return_tensors="pt"
      )
  
      self.model_fp16 = self.model_fp16.to(torch.float32)
      _ = self.model_fp16.generate(
          input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10
      )
  
      # Check this does not throw an error
      _ = self.model_fp16.to("cpu")
  
      # Check this does not throw an error
      _ = self.model_fp16.half()
  
      # Check this does not throw an error
      _ = self.model_fp16.float()
  
imports: import gc
  import importlib.metadata
  import tempfile
  import unittest
  from packaging import version
  from transformers import AutoConfig, AutoModel, AutoModelForCausalLM, AutoModelForSeq2SeqLM, AutoModelForSequenceClassification, AutoTokenizer, BitsAndBytesConfig, pipeline
  from transformers.testing_utils import is_bitsandbytes_available, is_torch_available, require_accelerate, require_bitsandbytes, require_torch, require_torch_gpu, require_torch_multi_gpu, slow, torch_device
label_desc: Use image node_id 11 for calling the Bnb4BitTest obj's underlying member method code with example usage: obj.test_device_and_dtype_assignment() without return types