[Bug] ModuleNotFoundError: No module named 'vllm.model_executor.model_loader.bitsandbytes_loader' #2983
Description
- Did you update?
pip install --upgrade unsloth unsloth_zoo✅ ColaborKaggleor local / cloud: Colab- Number GPUs used, use
nvidia-smi: Tesla T4 free env - Which notebook? Please link! https://colab.research.google.com/github/unslothai/notebooks/blob/main/nb/Qwen3_(4B)-GRPO.ipynb
- Which Unsloth version, TRL version, transformers version, PyTorch version? unsloth== 2025.7.4, unsloth-zoo==2025.7.6
Code to replicate
%%capture
import os
if "COLAB_" not in "".join(os.environ.keys()):
!pip install unsloth vllm
else:
# [NOTE] Do the below ONLY in Colab! Use [[pip install unsloth vllm]]
!pip install --no-deps unsloth vllm==0.8.5.post1
#@title Colab Extra Install { display-mode: "form" }
%%capture
import os
if "COLAB_" not in "".join(os.environ.keys()):
!pip install unsloth vllm
else:
!pip install --no-deps unsloth vllm==0.8.5.post1
# [NOTE] Do the below ONLY in Colab! Use [[pip install unsloth vllm]]
# Skip restarting message in Colab
import sys, re, requests; modules = list(sys.modules.keys())
for x in modules: sys.modules.pop(x) if "PIL" in x or "google" in x else None
!pip install --no-deps bitsandbytes accelerate xformers==0.0.29.post3 peft trl triton cut_cross_entropy unsloth-zoo
!pip install sentencepiece protobuf "datasets>=3.4.1,<4.0.0" huggingface_hub hf_transfer
# vLLM requirements - vLLM breaks Colab due to reinstalling numpy
f = requests.get("https://raw.githubusercontent.com/vllm-project/vllm/refs/heads/main/requirements/common.txt").content
with open("vllm_requirements.txt", "wb") as file:
file.write(re.sub(rb"(transformers|numpy|xformers)[^\n]{1,}\n", b"", f))
!pip install -r vllm_requirements.txtfrom unsloth import FastLanguageModelError
🦥 Unsloth: Will patch your computer to enable 2x faster free finetuning.
🦥 Unsloth Zoo will now patch everything to make training faster!
INFO 07-17 16:03:10 [importing.py:53] Triton module has been replaced with a placeholder.
INFO 07-17 16:03:10 [__init__.py:239] Automatically detected platform cuda.
---------------------------------------------------------------------------
ModuleNotFoundError Traceback (most recent call last)
[/tmp/ipython-input-3-3010846500.py](https://localhost:8080/#) in <cell line: 0>()
----> 1 from unsloth import FastLanguageModel
2 import torch
3 max_seq_length = 2048 # Can increase for longer reasoning traces
4 lora_rank = 32 # Larger rank = smarter, but slower
5
4 frames
[/usr/local/lib/python3.11/dist-packages/unsloth/__init__.py](https://localhost:8080/#) in <module>
241 pass
242
--> 243 from .models import *
244 from .models import __version__
245 from .save import *
[/usr/local/lib/python3.11/dist-packages/unsloth/models/__init__.py](https://localhost:8080/#) in <module>
13 # limitations under the License.
14
---> 15 from .llama import FastLlamaModel
16 from .loader import FastLanguageModel, FastVisionModel, FastTextModel, FastModel
17 from .mistral import FastMistralModel
[/usr/local/lib/python3.11/dist-packages/unsloth/models/llama.py](https://localhost:8080/#) in <module>
48 if HAS_FLASH_ATTENTION:
49 from flash_attn import flash_attn_func
---> 50 from .vision import FastBaseModel
51
52 # Final patching code
[/usr/local/lib/python3.11/dist-packages/unsloth/models/vision.py](https://localhost:8080/#) in <module>
81 _compile_config.disable = True # Must set manually
82
---> 83 from unsloth_zoo.vllm_utils import (
84 convert_lora_modules,
85 return_lora_modules,
[/usr/local/lib/python3.11/dist-packages/unsloth_zoo/vllm_utils.py](https://localhost:8080/#) in <module>
101 return quant_states
102
--> 103 import vllm.model_executor.model_loader.bitsandbytes_loader
104 if hasattr(
105 vllm.model_executor.model_loader.bitsandbytes_loader,
ModuleNotFoundError: No module named 'vllm.model_executor.model_loader.bitsandbytes_loader'
---------------------------------------------------------------------------
NOTE: If your import is failing due to a missing package, you can
manually install dependencies using either !pip or !apt.
To view examples of installing some common dependencies, click the
"Open Examples" button below.
---------------------------------------------------------------------------
Solution that worked for me: downgrade to unsloth==2025.7.3, unsloth-zoo==2025.7.4