无法修复 Python 错误 AttributeError: 'int' object 没有属性 'get'

Question

My source code

def display_inventory(inventory):
    print("Itme list")
    item_total = 0
    for k,v in inventory.items():
        print(str(k) + str(v))
        item_total = item_total + v.get(k,0)
    print("The total number of items:" + str(item_total))

stuff = {'rope':1, 'torch':6, 'coin':42, 'Shuriken':1, 'arrow':12}
display_inventory(stuff)

error message

AttributeError: 'int' object has no attribute 'get'

Could you please tell me how I can fix this error? I'd appreciate if you could also explain why this doesn't work.

thank you in advance

Answer 1

1. get should be called on the dictionary (ie inventory ).
2. There is no need to call get because v = inventory[k] in the loop.
3. You do not need to have a default in case k does not exist because for k,v in inventory.items() only loops through existing items.

Answer 2

Why don't you simply write the following:

def display_inventory(inventory):
    print("Itme list")
    item_total = 0
    for k,v in inventory.items():
        print(str(k) + str(v))
        item_total = item_total + v  # <<< CHANGE HERE
    print("The total number of items:" + str(item_total))

stuff = {'rope':1, 'torch':6, 'coin':42, 'Shuriken':1, 'arrow':12}
display_inventory(stuff)

Because in this cause the value v is the number corresponding to the product which you want to add up. There is no need to make any further dictionary lookups using get() because you already have the value you need.

Answer 3

In your dictionary, v is an integer. Everything in the dictionary is fetched in inventory.items() .And you are trying to fetch something from an intege. Hence it shows an error. The solution is simply change to v

def display_inventory(inventory: dict):
    print("Item list")
    item_total = 0
    for k,v in inventory.items():
        print(str(k) + str(v))
        item_total = item_total + v #=== Here
    print("The total number of items:" + str(item_total))

stuff = {'rope':1, 'torch':6, 'coin':42, 'Shuriken':1, 'arrow':12}
display_inventory(stuff)

And the output:

rope1
torch6
coin42
Shuriken1
arrow12
The total number of items:62

Answer 4

The bug is in the line with v.get(k,0) . The syntax for .get() function is

<dict>.get(<key>, <default value if key not found> and outputs a value in the dictionary,

whereas the usual <dict>[<key>] method would throw an error if the key is not present.

Specific to your code when iterating through the key-value pair for k,v in inventory.items(): , the key is guaranteed to be present.

And since you are already iterating through the values in the dictionary, so you could simply use

item_total += v .

Additional feedback on print(str(k) + str(v)) , you could try the following:

1. Use + notation print(str(k) + ' ' + str(v)) which allows only string
2. Or use , notation print(k, v) which allows a mix of string and list
3. Use , notation in print("The total number of items:", item_total)

Output

rope 1
torch 6
coin 42
Shuriken 1
arrow 12
The total number of items: 62

By the way there is a typo in print("Itme list") .

Cheers!