python p1

#This program calcualtes the cost of an appliance
#it will calculate the cost of 10 minutes, 1 hour, 1 day
watts = float(input("How many watts does your appliance use:" ))
price = float(input("How much does your power cost in KW/h:"))
while not str(watts):
        if not watts:
                print("You can not enter no watts.")
                watts = float(input("How many watts does your appliance use:")
if str(price) == ("")
        float(price) = 8.2 #cents
hour = watts * price
min = ((hour / 60) * 10 # ten minutes
day = hour * 24
print("Your appliance would cost you " + str(min) + " cents for 10 minutes.")
print( str(hour) + " cents for one hour.")
print( str(day) + " cents for one day.")