utils.py

import plotly.graph_objects as go
import numpy as np

def list_supported_models(task):
    if task == "Text Classification":
        return ["distilbert-base-uncased", "bert-base-uncased", "roberta-base"]
    elif task == "Text Generation":
        return ["gpt2", "distilgpt2"]
    elif task == "Question Answering":
        return ["deepset/roberta-base-squad2", "distilbert-base-cased-distilled-squad"]
    return []

def visualize_attention(attentions, tokenizer, inputs):
    tokens = tokenizer.convert_ids_to_tokens(inputs["input_ids"][0])
    last_layer_attention = attentions[-1][0]  # shape: [num_heads, seq_len, seq_len]
    avg_attention = last_layer_attention.mean(dim=0).detach().numpy()
    
    fig = go.Figure(data=go.Heatmap(
        z=avg_attention,
        x=tokens,
        y=tokens,
        colorscale='Viridis'
    ))
    fig.update_layout(title="Average Attention - Last Layer", xaxis_nticks=len(tokens))
    return fig