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			77 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			77 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| # Copyright (c) Sebastian Raschka under Apache License 2.0 (see LICENSE.txt).
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| # Source for "Build a Large Language Model From Scratch"
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| #   - https://www.manning.com/books/build-a-large-language-model-from-scratch
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| # Code: https://github.com/rasbt/LLMs-from-scratch
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| 
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| from pathlib import Path
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| import sys
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| 
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| import tiktoken
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| import torch
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| import chainlit
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| 
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| from previous_chapters import (
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|     generate,
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|     GPTModel,
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|     text_to_token_ids,
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|     token_ids_to_text,
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| )
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| 
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| device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
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| 
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| 
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| def get_model_and_tokenizer():
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|     """
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|     Code to load a GPT-2 model with pretrained weights generated in chapter 5.
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|     This requires that you run the code in chapter 5 first, which generates the necessary model.pth file.
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|     """
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| 
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|     GPT_CONFIG_124M = {
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|         "vocab_size": 50257,    # Vocabulary size
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|         "context_length": 256,  # Shortened context length (orig: 1024)
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|         "emb_dim": 768,         # Embedding dimension
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|         "n_heads": 12,          # Number of attention heads
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|         "n_layers": 12,         # Number of layers
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|         "drop_rate": 0.1,       # Dropout rate
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|         "qkv_bias": False       # Query-key-value bias
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|     }
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| 
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|     tokenizer = tiktoken.get_encoding("gpt2")
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| 
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|     model_path = Path("..") / "01_main-chapter-code" / "model.pth"
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|     if not model_path.exists():
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|         print(f"Could not find the {model_path} file. Please run the chapter 5 code (ch05.ipynb) to generate the model.pth file.")
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|         sys.exit()
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| 
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|     checkpoint = torch.load(model_path, weights_only=True)
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|     model = GPTModel(GPT_CONFIG_124M)
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|     model.load_state_dict(checkpoint)
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|     model.to(device)
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| 
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|     return tokenizer, model, GPT_CONFIG_124M
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| 
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| 
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| # Obtain the necessary tokenizer and model files for the chainlit function below
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| tokenizer, model, model_config = get_model_and_tokenizer()
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| 
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| 
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| @chainlit.on_message
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| async def main(message: chainlit.Message):
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|     """
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|     The main Chainlit function.
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|     """
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|     token_ids = generate(  # function uses `with torch.no_grad()` internally already
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|         model=model,
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|         idx=text_to_token_ids(message.content, tokenizer).to(device),  # The user text is provided via as `message.content`
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|         max_new_tokens=50,
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|         context_size=model_config["context_length"],
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|         top_k=1,
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|         temperature=0.0
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|     )
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| 
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|     text = token_ids_to_text(token_ids, tokenizer)
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| 
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|     await chainlit.Message(
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|         content=f"{text}",  # This returns the model response to the interface
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|     ).send()
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