holding if/else condition in live bitcoin trading Python

[Arshpreet Singh]

I am making a function that is running in while loop and if/else statements make decisions on based on the condition:
here is code:


def main_call():
    while True:
        l0_0 = getDiff('btcusd',8)
        l1_0 = np.tanh(l0_0*0.8446488687)

        l1_1 = np.tanh(l0_0*-0.5674069006)
        l1_2 = np.tanh(l0_0*0.8676766445)

<lots of calculation here to get value of l3_0>          
        if(l3_0>0):
            print l3_0
            print auto_order_buy('0.01',str(ticker_last('btcusd')))
        elif(l3_0<0):
            print l3_0
            print auto_order_sell('0.01',str(ticker_last('btcusd')))
        else:
            pass
            
now in my function l3_0>0 auto_order_buy() is executed but as program is running in while loop so it gets executed again and again. I have implemented while loop because I am doing live trading. is there any approach I can go with so auto_order_buy() auto_order_sell() function only executed once?