Python: Error = Class 'Foo' has no 'bar' member? -

i receiving error:

attributeerror: type object 'shop' has no attribute 'inventory'

my class set:

class shop(object):     def __init__(self, name, inventory, margin, profit):         self.name = name          self.inventory = inventory         self.margin = margin         self.profit = profit   # initial inventory including 2 of each 6 models available inventory = 12 # markup of 20% on sales margin = .2 # revenue minus cost after sale bike in bikes.values():     profit = bike.cost * margin 

and want print inventory:

print "mike's bikes has {} bikes in stock.".format(shop.inventory) 

but keep getting same error. can make work with:

print "mike's bikes has %d bikes in stock." % (inventory) 

but trying make switch .format()

you never created instance of class, shop.__init__() method never run either.

your class doesn't have such attribute; attribute defined shop class __init__ method itself.

create instance of class, attribute on instance:

# initial inventory including 2 of each 6 models available inventory = 12 # markup of 20% on sales margin = .2 # revenue minus cost after sale bike in bikes.values():     profit = bike.cost * margin  bikeshop = shop("mike's bikes", inventory, margin, profit) print "mike's bikes has {} bikes in stock.".format(bikeshop.inventory) 

in creating instance shop(....), python created instance , called __init__ method on instance. result, inventory attribute added instance, , can access via bikeshop.inventory.