Format timestamp for human consumption.

def pretty_time(timestamp: str):
    """Format timestamp for human consumption."""
    try:
        parsed = iso_8601.parse_datetime(timestamp)
    except ValueError:
        now = datetime.utcnow().replace(tzinfo=timezone.utc)
        try:
            delta = iso_8601.parse_delta(timestamp)
        except ValueError:
            delta = human_time.parse_timedelta(timestamp)
        parsed = now - delta

    echo(human_time.human_timestamp(parsed))