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Goekdeniz-Guelmez 2025-03-01 12:47:13 +01:00
parent 8aeea10901
commit c119a7a4a5

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@ -2,48 +2,103 @@ import itertools
import json
import types
from pathlib import Path
from typing import Any, Dict, List, Optional
from typing import Any, Dict, List, Union
from transformers import PreTrainedTokenizer
class DPODataset:
"""
A dataset for DPO (Direct Preference Optimization) training that handles
prompt-chosen-rejected triplets in the format:
{"system": ..., "prompt": ..., "chosen": ..., "rejected": ...}
"""
def __init__(self, data: List[Dict[str, str]], tokenizer: PreTrainedTokenizer,
prompt_key: str = "prompt", chosen_key: str = "chosen",
rejected_key: str = "rejected", system_key: str = "system"):
def __init__(
self,
data: List[Dict[str, Union[str, Dict, List]]],
tokenizer: PreTrainedTokenizer,
prompt_key: str = "prompt",
chosen_key: str = "chosen",
rejected_key: str = "rejected",
system_key: str = None
):
self._chosen_data = []
self._rejected_data = []
for d in data:
messages = (
[{"role": "system", "content": d[system_key]}] if system_key and system_key in d else []
)
messages.append({"role": "user", "content": d[prompt_key]})
# Get prompt content, preferring 'prompt' over 'question'
prompt_content = d.get(prompt_key, d.get("question", ""))
# Apply template once for each response type
base_messages = messages.copy()
chosen_messages = base_messages + [{"role": "assistant", "content": d[chosen_key]}]
rejected_messages = base_messages + [{"role": "assistant", "content": d[rejected_key]}]
if system_key and system_key in d:
base_messages = [{"role": "system", "content": d[system_key]}]
chosen_messages = base_messages + [{"role": "user", "content": prompt_content}]
rejected_messages = base_messages + [{"role": "user", "content": prompt_content}]
# Handle chosen messages
if isinstance(d[chosen_key], str):
chosen_messages.append({"role": "assistant", "content": d[chosen_key]})
elif isinstance(d[chosen_key], dict):
if "messages" in d[chosen_key]:
chosen_messages.extend(d[chosen_key]["messages"])
else:
chosen_messages.append({"role": "assistant", "content": d[chosen_key].get("content", "")})
elif isinstance(d[chosen_key], list):
chosen_messages.extend(d[chosen_key])
# Handle rejected messages
if isinstance(d[rejected_key], str):
rejected_messages.append({"role": "assistant", "content": d[rejected_key]})
elif isinstance(d[rejected_key], dict):
if "messages" in d[rejected_key]:
rejected_messages.extend(d[rejected_key]["messages"])
else:
rejected_messages.append({"role": "assistant", "content": d[rejected_key].get("content", "")})
elif isinstance(d[rejected_key], list):
rejected_messages.extend(d[rejected_key])
chosen_text = tokenizer.apply_chat_template(chosen_messages)
rejected_text = tokenizer.apply_chat_template(rejected_messages)
self._chosen_data.append(tokenizer.apply_chat_template(chosen_messages))
self._rejected_data.append(tokenizer.apply_chat_template(rejected_messages))
else:
# Handle non-system message cases
chosen_content = self._extract_content(d[chosen_key])
rejected_content = self._extract_content(d[rejected_key])
chosen_text = tokenizer.apply_chat_template([
{"role": "user", "content": prompt_content},
{"role": "assistant", "content": chosen_content},
])
rejected_text = tokenizer.apply_chat_template([
{"role": "user", "content": prompt_content},
{"role": "assistant", "content": rejected_content},
])
self._chosen_data.append(chosen_text)
self._rejected_data.append(rejected_text)
def _extract_content(self, data):
"""Helper method to extract content from various data formats."""
if isinstance(data, str):
return data
elif isinstance(data, dict):
if "messages" in data:
last_message = data["messages"][-1]
return last_message.get("content", last_message.get("messages", ""))
return data.get("content", "")
elif isinstance(data, list):
last_message = data[-1]
if isinstance(last_message, dict):
if "content" in last_message:
return last_message["content"]
elif "messages" in last_message:
return last_message["messages"]
return last_message if isinstance(last_message, str) else ""
return ""
def __len__(self):
return len(self._chosen_data)
def __getitem__(self, idx: int):
return {
"chosen": self._chosen_data[idx],
"rejected": self._rejected_data[idx]
}
def __len__(self):
return len(self._chosen_data)
class Dataset:
"""
Light-weight wrapper to hold a dataset.