Python OOPS Class with dictionary

Question

Data Structure

myshelf = {}
myshelf["PY"] ={}
myshelf["PY"]["WWW"] = {"Name": "Book1", "Class": "5th"}
myshelf["PY"]["XXX"] = {"Name": "Book2", "Class": "6th"}
myshelf["EE"] ={}
myshelf["EE"]["YYY"] = {"Name": "Book3", "Class": "7th"}
myshelf["EE"]["ZZZ"] = {"Name": "Book4", "Class": "8th"}
print(myshelf) 
for shelfkey in myshelf.keys():
for subshelf in myshelf[shelfkey].keys():
    print(myshelf[shelfkey][subshelf])

here is output of above code , which means my data structure is ok.

{'PY': {'WWW': {'Name': 'Book1', 'Class': '5th'}, 'XXX': {'Name': 'Book2', 'Class': '6th'}}, 'EE': {'YYY': {'Name': 'Book3', 'Class': '7th'}, 'ZZZ': {'Name': 'Book4', 'Class': '8th'}}}
{'Name': 'Book1', 'Class': '5th'}
{'Name': 'Book2', 'Class': '6th'}
{'Name': 'Book3', 'Class': '7th'}
{'Name': 'Book4', 'Class': '8th'}

Now i have a csv file which contains books , I want to arrange all the books into my shelved . Note myShelf have SubShelf . ShelfName is 2 letter capital of book name and my Subshelf have ISBN number of book. (Consider that ISBN number for particular book will remain same and will never change)

CSV FILE FORMAT

1   A11B12C13D14    Python Expert   English India   Raj     500 2
2   A11B12C13D14    Python Expert   English India   Raj     500 2
3   A11B12C13D14    Python Expert   English India   Raj     500 2
4   A11B12C13D16    Python Advanced English USA Amit    40000   1
5   A11B12C13D17    Aws Arch    English USA Sumit   40000   1

Now here is my main code

import csv

class Book:

def __init__(self, isbn, name, language, origin, authors, price, version):
    self.isbn = isbn
    self.name = name
    self.language = language
    self.origin = origin
    self.authors = authors
    self.price = price
    self.version = version
    self.counter= 1


class Shelf:
    def __init__(self, mycsvfilepath):
        self.shelf = {}
        self.mycsvfilepath = mycsvfilepath


        def _add_books_(self):
    with open(self.mycsvfilepath, "rt") as my_csv_file:
        my_csv_reader = csv.reader(my_csv_file)
        for line in my_csv_reader:
            mykeyforshelf = line[2][0:2].upper()
            print("ShelfName ={}".format(mykeyforshelf))
            print("SubShelfName={}".format(line[1]))
            if mykeyforshelf not in self.shelf.keys():
                self.shelf[mykeyforshelf] = {}
                self.shelf[mykeyforshelf][line[1]] = Book(line[1],line[2],line[3],line[4],line[5],line[6],line[7])
                print("Added New Book to new shelf ={} , subshelf= {}, BookName= {}".format(mykeyforshelf,line[1],self.shelf[mykeyforshelf][line[1]].name))
                print(self.shelf)
                print("\n")
            elif line[1] in self.shelf[mykeyforshelf].keys():
                print("this is existing shelf = {} and subshelf={}".format(mykeyforshelf,line[1]))
                print("existing counter for this book = {}".format(self.shelf[mykeyforshelf][line[1]].counter))
                self.shelf[mykeyforshelf][line[1]].counter = self.shelf[mykeyforshelf][line[1]].counter + 1
                print("New counter for this book = {}".format(self.shelf[mykeyforshelf][line[1]].counter))
                print(self.shelf)
                print("\n")
            else:
                print("I am existing shelf = {} , But new Sub Shelf ={}".format(mykeyforshelf,line[1]))
                self.shelf[mykeyforshelf][line[1]] = Book(line[1],line[2],line[3],line[4],line[5],line[6],line[7])
                print(self.shelf)
                print("\n")


myShelfObj = Shelf("E:\\Ashish\MyCsvFiles\\myCurrentInventory.csv")
myShelfObj._add_books_()
print("_____________________________________________________________")
print(myShelfObj)
print(type(myShelfObj))

#for shelfkey in myShelfObj:
#    for subshelf in myShelfObj.shelfkey:
#        print(myShelfObj[shelfkey][subshelf])

myCode is working file if i keep above 3 lines hashed marked. Here is output of working code.

ShelfName =PY
SubShelfName=A11B12C13D14
Added New Book to new shelf =PY , subshelf= A11B12C13D14, BookName= Python 
Expert
{'PY': {'A11B12C13D14': <__main__.Book object at 0x000000FC39A1C940>}}


ShelfName =PY
SubShelfName=A11B12C13D14
this is existing shelf = PY and subshelf=A11B12C13D14
existing counter for this book = 1
New counter for this book = 2
{'PY': {'A11B12C13D14': <__main__.Book object at 0x000000FC39A1C940>}}


ShelfName =PY
SubShelfName=A11B12C13D14
this is existing shelf = PY and subshelf=A11B12C13D14
existing counter for this book = 2
New counter for this book = 3
{'PY': {'A11B12C13D14': <__main__.Book object at 0x000000FC39A1C940>}}


ShelfName =PY
SubShelfName=A11B12C13D16
I am existing shelf = PY , But new Sub Shelf =A11B12C13D16
{'PY': {'A11B12C13D14': <__main__.Book object at 0x000000FC39A1C940>, 
'A11B12C13D16': <__main__.Book object at 0x000000FC39A1CA58>}}


ShelfName =AW
SubShelfName=A11B12C13D17
Added New Book to new shelf =AW , subshelf= A11B12C13D17, BookName= Aws Arch
{'PY': {'A11B12C13D14': <__main__.Book object at 0x000000FC39A1C940>, 
'A11B12C13D16': <__main__.Book object at 0x000000FC39A1CA58>}, 'AW': 
{'A11B12C13D17': <__main__.Book object at 0x000000FC39A1CAC8>}}


_____________________________________________________________________________
<__main__.Shelf object at 0x000000FC399C9748>
<class '__main__.Shelf'>

But as i mentioned above if i unhash last 3 lines it gives me below mentioned error:

for shelfkey in myShelfObj:
TypeError: 'Shelf' object is not iterable

Please help me.

i have changed my code a bit and instead of initializing a shelf in the class , I created it as a Global variable and it is working now for me without any issue. — user8588795
– user8588795, Commented Jul 31, 2018 at 0:10
But my question is unanswered. what was wrong in my first approch — user8588795
– user8588795, Commented Jul 31, 2018 at 0:11

Nikhil Rathore · Accepted Answer · 2018-07-31 01:24:16Z

1

See as you can see for yourself when you are typing the type of myShelfObj it is coming to be

print(type(myShelfObj))

Here is the output

<class '__main__.Shelf'>

So you are trying to iterate through a object which is not possible. You will get such error. You can only use for loops with list tuple dictionary but not an object. Hope I am clear

answered Jul 31, 2018 at 1:24

Nikhil Rathore

1703 silver badges15 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Python OOPS Class with dictionary

1 Answer 1

Comments

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Related