strategy(title='饥饿者~01', overlay=true, 
     pyramiding=0, default_qty_type=strategy.cash, 
     default_qty_value=1, initial_capital=100, 
     currency=currency.USD, commission_value=0.05, 
     commission_type=strategy.commission.percent, 
     process_orders_on_close=true)
//对上面这段话的解释：策略标题（名字）“”，显示在图表（主图），pyramiding=0只能在同一方向上开单，......


//-------------- fetch user inputs ------------------
gain = input.float(title="Kalman Gain:", defval=100.0, minval=1, maxval=10000.0, step=1)
src = input(defval=close, title='Source:')