AsyncSet.py

import asyncio

class AsyncSet:
    """Thread/async-safe set."""
    
    def __init__(self):
        self._items = set()
        self._lock = asyncio.Lock()
    
    async def add(self, item):
        """Add item to set."""
        async with self._lock:
            self._items.add(item)
    
    async def discard(self, item):
        """Remove item if present."""
        async with self._lock:
            self._items.discard(item)
    
    async def remove(self, item):
        """Remove item, raise KeyError if not present."""
        async with self._lock:
            self._items.remove(item)
    
    async def pop(self):
        """Remove and return arbitrary item."""
        async with self._lock:
            return self._items.pop()
    
    async def clear(self):
        """Remove all items."""
        async with self._lock:
            self._items.clear()
    
    async def copy(self):
        """Return a copy of the set."""
        async with self._lock:
            return self._items.copy()
    
    def __contains__(self, item):
        """Check if item in set."""
        return item in self._items
    
    def __len__(self):
        """Get size of set."""
        return len(self._items)

    def __bool__(self):
        """Check if set is empty in pythonic way"""
        return bool(self._items)