import random
from datetime import datetime, timezone

def jitter(interval: float) -> float:
    """
    Returns a value within interval ± 10%
    """
    variation = interval * 0.10
    return interval + random.uniform(-variation, variation)

def now_utc() -> datetime:
    """
    Returns the current UTC datetime with timezone info.
    """
    return datetime.now(timezone.utc)