Error in "Veneer" Project in Python

I was trying to complete “Veneer” Project on Python 3. When I Run the following code:

class Art:
def init(self, artist, title, medium, year, owner):
self.owner = owner
self.artist = artist
self.title = title
self.medium = medium
self.year = year

def __repr__(self):
    return '%s. "%s". %s, %s, %s, %s.' % (self.artist, self.title, self.year, self.medium,,self.owner.location )

class Listing:
def init(self,art,price,seller): =art
self.price = price
self.seller = seller

def __repr__(self):
    return '%s, %s.' % (, self.price)

class Marketplace:
def init(self):
self.listings =

def add_listing(self,new_listing):

def remove_listing(self,expired_listing):

def show_listings(self):
    for item in self.listings:

veneer = Marketplace

class Client:
def init(self, name, location, is_museum): = name
self.is_museum = is_museum
if is_museum:
self.location = location
self.location = “Private Collection”

def sell_artwork(self,artwork,price):
    if artwork.owner == self:
        new_listing = Listing(artwork,price,artwork.owner)

edytta = Client(“Edytta Halpirt”,None,False)
moma = Client(“The MOMA”,“New York”,True)

girl_with_mandolin = Art(“Picasso, Pablo”, “Girl with a Mandolin (Fanny Tellier)”, “oil on canvas”, 1910,edytta)

edytta.sell_artwork(girl_with_mandolin,"$6M USD")

I get an Error:

Traceback (most recent call last):
File “”, line 67, in
edytta.sell_artwork(girl_with_mandolin,"$6M USD")
File “”, line 56, in sell_artwork
TypeError: add_listing() missing 1 required positional argument: ‘new_listing’

I am unable to figure out the error. can anyone help.

Hello, @chip5467983175, and welcome to the Codecademy Forums!

Your code is not completely formatted for posting, so it does not display all of its indentations and other important details. For advice on how to format code when you post it, see How to ask good questions (and get good answers).

You have this line in your code:

veneer = Marketplace

Because it does not include parentheses after the class name, it fails to create an instance of Marketplace. Instead, it merely assigns a reference to the definition of the Marketplace class to veneer. As a consequence, when you attempt to call the add_listing method from veneer later, within the sell_artwork method definition of the Client class, the Python interpreter expects an argument that represents an instance of Marketplace to be included. When it finds only one argument within the parentheses there, a TypeError is raised.

To correct that problem, just add the parentheses to the line cited above, where you intend to instantiate Marketplace.

Also note that in your final line of code, the show_listings method of veneer will not actually get called, unless you add parentheses at the end of that line.

Edited on August 29, 2019 to add the following:

Link to project: Veneer

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