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--description--

Complete the Category class. It should be able to instantiate objects based on different budget categories like food, clothing, and entertainment. When objects are created, they are passed in the name of the category. The class should have an instance variable called ledger that is a list. The class should also contain the following methods:

  • A deposit method that accepts an amount and description. If no description is given, it should default to an empty string. The method should append an object to the ledger list in the form of {'amount': amount, 'description': description}.
  • A withdraw method that is similar to the deposit method, but the amount passed in should be stored in the ledger as a negative number. If there are not enough funds, nothing should be added to the ledger. This method should return True if the withdrawal took place, and False otherwise.
  • A get_balance method that returns the current balance of the budget category based on the deposits and withdrawals that have occurred.
  • A transfer method that accepts an amount and another budget category as arguments. The method should add a withdrawal with the amount and the description 'Transfer to [Destination Budget Category]'. The method should then add a deposit to the other budget category with the amount and the description 'Transfer from [Source Budget Category]'. If there are not enough funds, nothing should be added to either ledgers. This method should return True if the transfer took place, and False otherwise.
  • A check_funds method that accepts an amount as an argument. It returns False if the amount is greater than the balance of the budget category and returns True otherwise. This method should be used by both the withdraw method and transfer method.

When the budget object is printed it should display:

  • A title line of 30 characters where the name of the category is centered in a line of * characters.
  • A list of the items in the ledger. Each line should show the description and amount. The first 23 characters of the description should be displayed, then the amount. The amount should be right aligned, contain two decimal places, and display a maximum of 7 characters.
  • A line displaying the category total.

Here is an example usage:

food = Category('Food')
food.deposit(1000, 'deposit')
food.withdraw(10.15, 'groceries')
food.withdraw(15.89, 'restaurant and more food for dessert')
clothing = Category('Clothing')
food.transfer(50, clothing)
print(food)

And here is an example of the output:

*************Food*************
initial deposit        1000.00
groceries               -10.15
restaurant and more foo -15.89
Transfer to Clothing    -50.00
Total: 923.96

Besides the Category class, create a function (outside of the class) called create_spend_chart that takes a list of categories as an argument. It should return a string that is a bar chart.

The chart should show the percentage spent in each category passed in to the function. The percentage spent should be calculated only with withdrawals and not with deposits. Down the left side of the chart should be labels 0 - 100. The 'bars' in the bar chart should be made out of the 'o' character. The height of each bar should be rounded down to the nearest 10. The horizontal line below the bars should go two spaces past the final bar. Each category name should be written vertically below the bar. There should be a title at the top that says 'Percentage spent by category'.

This function will be tested with up to four categories.

Look at the example output below very closely and make sure the spacing of the output matches the example exactly.

Percentage spent by category
100|          
 90|          
 80|          
 70|          
 60| o        
 50| o        
 40| o        
 30| o        
 20| o  o     
 10| o  o  o  
  0| o  o  o  
    ----------
     F  C  A  
     o  l  u  
     o  o  t  
     d  t  o  
        h     
        i     
        n     
        g

Note: open the browser console with F12 to see a more verbose output of the tests.

--hints--

The deposit method should create a specific object in the ledger instance variable.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
    
    def test_deposit(self):
        self.food.deposit(900, "deposit")
        actual = self.food.ledger[0]
        expected = {"amount": 900, "description": "deposit"}
        self.assertEqual(actual, expected, 'Expected "deposit" method to create a specific object in the ledger instance variable.')    
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

Calling the deposit method with no description should create a blank description.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
    
    def test_deposit_no_description(self):
        self.food.deposit(45.56)
        actual = self.food.ledger[0]
        expected = {"amount": 45.56, "description": ""}
        self.assertEqual(actual, expected, 'Expected calling "deposit" method with no description to create a blank description.')        
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

The withdraw method should create a specific object in the ledger instance variable.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
    
    def test_withdraw(self):
        self.food.deposit(900, "deposit")
        self.food.withdraw(45.67, "milk, cereal, eggs, bacon, bread")
        actual = self.food.ledger[1]
        expected = {"amount": -45.67, "description": "milk, cereal, eggs, bacon, bread"}
        self.assertEqual(actual, expected, 'Expected "withdraw" method to create a specific object in the ledger instance variable.')    
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

Calling the withdraw method with no description should create a blank description.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
    
    def test_withdraw_no_description(self):
        self.food.deposit(900, "deposit")
        good_withdraw = self.food.withdraw(45.67)
        actual = self.food.ledger[1]
        expected = {"amount": -45.67, "description": ""}
        self.assertEqual(actual, expected, 'Expected "withdraw" method with no description to create a blank description.')    
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

The withdraw method should return True if the withdrawal took place.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
    
    def test_withdraw_no_description(self):
        self.food.deposit(900, "deposit")
        good_withdraw = self.food.withdraw(45.67)
        self.assertEqual(good_withdraw, True, 'Expected "withdraw" method to return "True".')    
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

Calling food.deposit(900, 'deposit') and food.withdraw(45.67, 'milk, cereal, eggs, bacon, bread') should return a balance of 854.33.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
    
    def test_get_balance(self):
        self.food.deposit(900, "deposit")
        self.food.withdraw(45.67, "milk, cereal, eggs, bacon, bread")
        actual = self.food.get_balance()
        expected = 854.33
        self.assertEqual(actual, expected, 'Expected balance to be 854.33')    
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

Calling the transfer method on a category object should create a specific ledger item in that category object.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
        self.entertainment = budget.Category("Entertainment")
    
    def test_transfer(self):
        self.food.deposit(900, "deposit")
        self.food.withdraw(45.67, "milk, cereal, eggs, bacon, bread")
        transfer_amount = 20
        good_transfer = self.food.transfer(transfer_amount, self.entertainment)
        actual = self.food.ledger[2]
        expected = {"amount": -transfer_amount, "description": "Transfer to Entertainment"}
        self.assertEqual(actual, expected, 'Expected "transfer" method to create a specific ledger item in food object.')
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

The transfer method should return True if the transfer took place.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
        self.entertainment = budget.Category("Entertainment")
    
    def test_transfer(self):
        self.food.deposit(900, "deposit")
        self.food.withdraw(45.67, "milk, cereal, eggs, bacon, bread")
        transfer_amount = 20 
        good_transfer = self.food.transfer(transfer_amount, self.entertainment)        
        self.assertEqual(good_transfer, True, 'Expected "transfer" method to return "True".')        
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

Calling transfer on a category object should reduce the balance in the category object.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
        self.entertainment = budget.Category("Entertainment")
    
    def test_transfer(self):
        self.food.deposit(900, "deposit")
        self.food.withdraw(45.67, "milk, cereal, eggs, bacon, bread")
        transfer_amount = 20
        food_balance_before = self.food.get_balance()        
        good_transfer = self.food.transfer(transfer_amount, self.entertainment)
        food_balance_after = self.food.get_balance()
        self.assertEqual(food_balance_before - food_balance_after, transfer_amount, 'Expected "transfer" method to reduce balance in food object.')
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

The transfer method should increase the balance of the category object passed as its argument.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
        self.entertainment = budget.Category("Entertainment")
    
    def test_transfer(self):
        self.food.deposit(900, "deposit")
        self.food.withdraw(45.67, "milk, cereal, eggs, bacon, bread")
        transfer_amount = 20        
        entertainment_balance_before = self.entertainment.get_balance()
        good_transfer = self.food.transfer(transfer_amount, self.entertainment)        
        entertainment_balance_after = self.entertainment.get_balance()        
        self.assertEqual(entertainment_balance_after - entertainment_balance_before, transfer_amount, 'Expected "transfer" method to increase balance in entertainment object.')  
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

The transfer method should create a specific ledger item in the category object passed as its argument.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
        self.entertainment = budget.Category("Entertainment")
    
    def test_transfer(self):
        self.food.deposit(900, "deposit")
        self.food.withdraw(45.67, "milk, cereal, eggs, bacon, bread")
        transfer_amount = 20        
        good_transfer = self.food.transfer(transfer_amount, self.entertainment)
        actual = self.entertainment.ledger[0]
        expected = {"amount": transfer_amount, "description": "Transfer from Food"}
        self.assertEqual(actual, expected, 'Expected "transfer" method to create a specific ledger item in entertainment object.')    
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

The check_funds method should return False if the amount passed to the method is greater than the category balance.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
    
    def test_check_funds(self):
        self.food.deposit(10, "deposit")
        actual = self.food.check_funds(20)
        expected = False
        self.assertEqual(actual, expected, 'Expected "check_funds" method to be False')   
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

The check_funds method should return True if the amount passed to the method is not greater than the category balance.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
    
    def test_check_funds(self):
        self.food.deposit(10, "deposit")
        actual = self.food.check_funds(10)
        expected = True
        self.assertEqual(actual, expected, 'Expected "check_funds" method to be True')    
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

The withdraw method should return False if the withdrawal didn't take place.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
    
    def test_withdraw_no_funds(self):
        self.food.deposit(100, "deposit")
        good_withdraw = self.food.withdraw(100.10)
        self.assertEqual(good_withdraw, False, 'Expected "withdraw" method to return "False".')    
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

The transfer method should return False if the transfer didn't take place.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
        self.entertainment = budget.Category("Entertainment")
    
    def test_transfer_no_funds(self):
        self.food.deposit(100, "deposit")
        good_transfer = self.food.transfer(200, self.entertainment)
        self.assertEqual(good_transfer, False, 'Expected "transfer" method to return "False".')    
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

Printing a Category instance should give a different string representation of the object.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
        self.entertainment = budget.Category("Entertainment")
    
    def test_to_string(self):
        self.food.deposit(900, "deposit")
        self.food.withdraw(45.67, "milk, cereal, eggs, bacon, bread")
        self.food.transfer(20, self.entertainment)
        actual = str(self.food)
        expected = "*************Food*************\\ndeposit                 900.00\\nmilk, cereal, eggs, bac -45.67\\nTransfer to Entertainme -20.00\\nTotal: 834.33"
        self.assertEqual(actual, expected, 'Expected different string representation of object.')
`);
    const testCode = `
from unittest import main
from importlib import reload
import test_module

reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`
    const out = runPython(testCode);
    assert(out);
  }
})

create_spend_chart should print a different chart representation. Check that all spacing is exact.

({
  test: () => {
    pyodide.FS.writeFile('/home/pyodide/budget.py', code);
    pyodide.FS.writeFile('/home/pyodide/test_module.py',`
import unittest
import budget
from importlib import reload

reload(budget)
class UnitTests(unittest.TestCase):
    maxDiff = None
    def setUp(self):
        self.food = budget.Category("Food")
        self.entertainment = budget.Category("Entertainment")
        self.business = budget.Category("Business")
    
    def test_create_spend_chart(self):
        self.food.deposit(900, "deposit")
        self.entertainment.deposit(900, "deposit")
        self.business.deposit(900, "deposit")
        self.food.withdraw(105.55)
        self.entertainment.withdraw(33.40)
        self.business.withdraw(10.99)
        actual = budget.create_spend_chart([self.business, self.food, self.entertainment])
        expected = "Percentage spent by category\\n100|          \\n 90|          \\n 80|          \\n 70|    o     \\n 60|    o     \\n 50|    o     \\n 40|    o     \\n 30|    o     \\n 20|    o  o  \\n 10|    o  o  \\n  0| o  o  o  \\n    ----------\\n     B  F  E  \\n     u  o  n  \\n     s  o  t  \\n     i  d  e  \\n     n     r  \\n     e     t  \\n     s     a  \\n     s     i  \\n           n  \\n           m  \\n           e  \\n           n  \\n           t  "
        self.assertEqual(actual, expected, 'Expected different chart representation. Check that all spacing is exact.')
`);

    const testCode = `
from unittest import main
from importlib import reload
import test_module
reload(test_module)
t = main(module='test_module', exit=False)
t.result.wasSuccessful()
`;
    const out = runPython(testCode);
    assert(out);
  }
})

--seed--

--seed-contents--​

class Category:
    pass

def create_spend_chart(categories):
    pass

--solutions--

class Category:

    def __init__(self, name):
        self.name = name
        self.ledger = []
        self.balance = 0
        self.spent = 0

    def __str__(self):
        first_line = f'{self.name.center(30, "*")}\n'
        lines = ''
        total = f'Total: {format(self.balance, ".2f")}'

        for n in range(len(self.ledger)):
            descr = self.ledger[n]["description"][:23]
            am = format(float(self.ledger[n]["amount"]), ".2f")[:7]
            lines = lines + f'{descr:<23}{am:>7}\n'

        return f'{first_line}{lines}{total}'

    def deposit(self, amount, description=''):
        self.ledger.append({
            'amount': float(amount),
            'description': description
        })
        self.balance = self.balance + float(amount)

    def withdraw(self, amount, description=''):
        if self.check_funds(amount):
            self.ledger.append({
                'amount': -float(amount),
                'description': description
            })
            self.balance = self.balance - float(amount)
            self.spent = self.spent + float(amount)
            return True
        else:
            return False

    def get_balance(self):
        return self.balance

    def transfer(self, amount, category):
        if self.check_funds(amount):
            # withdraw
            self.ledger.append({
                'amount': -float(amount),
                'description': f'Transfer to {category.name}'
            })
            self.balance = self.balance - float(amount)
            # deposit
            category.deposit(amount, f'Transfer from {self.name}')

            return True
        else:
            return False

    def check_funds(self, amount):
        if float(amount) > self.balance:
            return False
        else:
            return True


def create_spend_chart(categories):
    total_expenses = 0
    obj = {}
    col1 = []
    str = []
    final_str = 'Percentage spent by category\n'
    label_max_length = 0
    label_strings = []

    for category in categories:
        total_expenses = total_expenses + category.spent
        obj[category.name] = {'expenses': category.spent}
        obj[category.name]['label'] = list(category.name)
        if len(obj[category.name]['label']) > label_max_length:
            label_max_length = len(obj[category.name]['label'])

    for category in categories:
        obj[category.name]['percent'] = (
            (category.spent / total_expenses * 100) // 10) * 10
        obj[category.name]['column'] = []
        for i in range(0, 110, 10):
            if obj[category.name]['percent'] >= i:
                obj[category.name]['column'].insert(0, 'o')
            else:
                obj[category.name]['column'].insert(0, ' ')

    for i in range(0, 110, 10):
        col1.insert(0, i)

    for i in range(11):
        str.append("")
        for key in obj:
            str[i] += (f'{obj[key]["column"][i]}  ')
        final_str += f'{col1[i]:>3}| {str[i]}\n'
    final_str += f'    {"-"*(1+3*len(obj))}\n   '

    for i in range(label_max_length):
        label_strings.append('  ')
        for k in obj:
            if len(obj[k]['label']) < label_max_length:
                obj[k]['label'].extend(
                    f'{" "*(label_max_length-len(obj[k]["label"]))}')

            label_strings[i] += f'{obj[k]["label"][i]}  '
        if i < label_max_length - 1:
            label_strings[i] += '\n   '
        final_str += label_strings[i]

    print(final_str)
    return (final_str)