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![Anthony Costanza](https://secure.gravatar.com/avatar/52e2fb624e5f378746d07a0d985c4a70?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Anthony Costanza
2,123 PointsGetting all kinds of errors -
Following the tutorial - not sure where I'm going wrong - ugh!
![Anthony Costanza](https://secure.gravatar.com/avatar/52e2fb624e5f378746d07a0d985c4a70?s=60&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Anthony Costanza
2,123 PointsTraceback (most recent call last):
File "/home/treehouse/workspace/shopping_list.py", line 32, in <module>
add_to_list(new_item)
File "/home/treehouse/workspace/shopping_list.py", line 8, in add_to_list
shopping_list.append(item)
AttributeError: 'dict' object has no attribute 'append'
![Anthony Costanza](https://secure.gravatar.com/avatar/52e2fb624e5f378746d07a0d985c4a70?s=60&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Anthony Costanza
2,123 PointsThank you guys !
But im a bit confused - I'm just following the assignment on Tree House - doing exactly what they are telling me to do - it works for the Treehouse instructor -
Here is the code:
shopping_list = {}
def add_to_list(item):
shopping_list.append(item)
print("Added! List has {} items.".format(len(shopping_list)))
def show_help(): print("What should we pick up at the store?") print(""" ENTER 'DONE' to stop adding items. Enter 'HELP' for this help. """)
show_help()
while True: new_item = input("> ")
if new_item == 'DONE':
break
elif new_item == 'HELP':
show_help()
continue
add_to_list(new_item)
![Anthony Costanza](https://secure.gravatar.com/avatar/52e2fb624e5f378746d07a0d985c4a70?s=60&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Anthony Costanza
2,123 PointsIsn't that what I have as my first line of code?
![Anthony Costanza](https://secure.gravatar.com/avatar/52e2fb624e5f378746d07a0d985c4a70?s=60&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Anthony Costanza
2,123 PointsOh! I have {} INSTEAD of [] - ugh!
so... the two are very different ?
![Anthony Costanza](https://secure.gravatar.com/avatar/52e2fb624e5f378746d07a0d985c4a70?s=60&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Anthony Costanza
2,123 PointsThank you!
Hopefully this does become second nature - but currently - I'm not convinced
Seems daunting
6 Answers
![AJ Tran](https://uploads.teamtreehouse.com/production/profile-photos/11571891/micro_aj.jpg)
AJ Tran
Treehouse TeacherHi there. Let's take a look at that last line of the error message:
AttributeError: 'dict' object has no attribute 'append'
The source of the error is this line of code:
shopping_list.append(item)
The error is telling us that shopping_list
is a Python Dictionary, which does not have a built-in method called .append()
!
You can use .append()
to add items to a Python List, but not a Python Dictionary.
To add a new key-value pair to a Dictionary, observe my examples below:
# Add by using bracket-notation
inventory = {
"apples": 1,
"bananas": 2
}
inventory["milk"] = 3
print(inventory)
# => {"apples": 1, "bananas": 2, "milk": 3}
# Add by using .update()
inventory = {
"apples": 1,
"bananas": 2
}
new_item = { "milk": 3 }
inventory.update(new_item)
print(inventory)
# => {"apples": 1, "banana": 2, "milk": 3}
![Jeff Muday](https://uploads.teamtreehouse.com/production/profile-photos/5900142/micro_jeff_face.jpg)
Jeff Muday
Treehouse Moderator 28,718 PointsYou beat me by a minute... good answer by the way! JM
![Jeff Muday](https://uploads.teamtreehouse.com/production/profile-photos/5900142/micro_jeff_face.jpg)
Jeff Muday
Treehouse Moderator 28,718 PointsCraig is asking you to create a new empty list called shopping_list
:
shopping_list = [] # create a new empty list with no items
But you can also do it like this:
shopping_list = list() # this is equivalent to the previous declaration
That should solve your issue.
![Jeff Muday](https://uploads.teamtreehouse.com/production/profile-photos/5900142/micro_jeff_face.jpg)
Jeff Muday
Treehouse Moderator 28,718 PointsLook carefully and you will see square brackets rather than curly braces. You can also use the list()
declaration like I showed in the second example.
![Jeff Muday](https://uploads.teamtreehouse.com/production/profile-photos/5900142/micro_jeff_face.jpg)
Jeff Muday
Treehouse Moderator 28,718 PointsOk, those messages do help me to know what is going on in your code.
One of the things I love about Python, well all computer languages in general is that there are numerous ways to write a program correctly. So you can inject your ideas and creativity in approaching problems.
The Error itself that is key is this-- "AttributeError: 'dict' object has no attribute 'append'"
Dictionary objects don't have an append()
method, but List objects do. Here's an example below...
shopping_list = [] # note the square brackets is an empty list
shopping_list.append('milk') # append milk...
shopping_list.append('eggs') # eggs...
shopping_list.append('bread') # bread
print(shopping_list)
The result is this.
['milk', 'eggs', 'bread']
As I mentioned above, you can write a project that is completely different and uses Dictionary objects which would work fine as well. However, you won't use append()
, but can use a key/value approach. The key is in the square bracket, and then we assign the key a string value, like milk, bread, or eggs! See below
shopping_list = {} # note the curly braces is an empty dict
shopping_list[0] = 'milk' # add 0/milk key value...
shopping_list[1] = 'eggs' # add 1/eggs...
shopping_list[2] = 'bread' # add 2/bread
print(shopping_list)
And so we have a dictionary that contains similar information, but structured a little differently!
{0: 'milk', 1: 'eggs', 2: 'bread'}
I hope this helps!
![Jeff Muday](https://uploads.teamtreehouse.com/production/profile-photos/5900142/micro_jeff_face.jpg)
Jeff Muday
Treehouse Moderator 28,718 PointsIt can definitely be confusing at first, but it will become second nature as you will use both dictionaries and list objects quite a bit.
Another cool structure is the set()
and the set is kind of like a list but doesn't allow for repeated elements and that can be super handy. And the set uses curly braces like the dictionary, but you will come upon that soon enough.
Good luck on your Python journey!!
![Jeff Muday](https://uploads.teamtreehouse.com/production/profile-photos/5900142/micro_jeff_face.jpg)
Jeff Muday
Treehouse Moderator 28,718 PointsRepetition is the key-- program a little every day and it will be your new friend. When I feel overwhelming stress (I'm looking at you 2020!) I will pick a quick project idea and hack away. My mind goes to an entirely different, calm place with Ruby, Python, or JavaScript as my toolkit! Yeah, I'm geeky like that.
Also... you should check out the website
Just in case you don't have your computer all set up for Python, you can go there and have Python workspaces. For example, you could put the Shopping List project there or anything else you are really proud of and you can share your code pretty easily with potential employers or clients.
Best of luck on your journey!
Jeff Muday
Treehouse Moderator 28,718 PointsJeff Muday
Treehouse Moderator 28,718 PointsAnthony, could you cut-an-paste the error messages into a reply? That would be a good starting point to solving your issue.