"""
Literature review implementation.
"""

from dataclasses import dataclass, field
from typing import List, Optional


@dataclass
class Paper:
    """Research paper data structure."""
    title: str
    abstract: str
    authors: List[str] = field(default_factory=list)
    year: Optional[int] = None

class LiteratureReviewer:
    """Literature review engine."""
    
    def __init__(self):
        self.papers = []
    
    def add_paper(self, paper: Paper) -> None:
        """Add a paper to review."""
        self.papers.append(paper)
    
    def generate_review(self) -> str:
        """Generate a literature review."""
        return f'Literature review of {len(self.papers)} papers.'
