# Dict Assertions

In this you'll learn how to use most used Dictionary assertion functions. Below are the functions that are covered.

assert_dict_variable_equals_variable(student_variable_name, expected_variable_name, delete_afterwards=True): Checks that the student's dictionary in student_variable_name matches the dictionary in expected_variable_name.
assert_dict_variable_equals_json(student_variable_name, json_file_name): Checks that the student's dictionary in student_variable_name matches the dictionary contained in the solution JSON file named json_file_name.
assert_dict_variable_equals_pickle(student_variable_name, pickle_file_name): Checks that the student's dictionary in student_variable_name matches the dictionary contained in the solution pickle file named pickle_file_name.

Load the utils.py file to use the assertion functions.

exec(open("utils.py").read())

# Activities

Now, with activities examples, you'll learn how to use the assertion functions.

We'll use the below fruits data for the activities.

fruits_data = [('apple', 'red', 0.99), ('banana', 'yellow', 0.59), ('orange', 'orange', 0.79), ('grape', 'purple', 1.29), ('kiwi', 'green', 1.09), ('pineapple', 'yellow', 1.99), ('strawberry', 'red', 0.69), ('watermelon', 'green', 2.49), ('mango', 'orange', 1.49), ('peach', 'orange', 1.79), ('pear', 'green', 0.89), ('plum', 'purple', 0.79), ('raspberry', 'red', 2.99), ('blueberry', 'blue', 3.99), ('blackberry', 'black', 4.99)]
fruits_data

# 1. Create a student dictionary

Use below data to create a dictionary named student_dict.

student_name = ['Albert', 'John', 'Peter', 'James', 'Robert']
student_age = [23, 24, 22, 25, 23]
student_city = ['New York', 'Los Angeles', 'Chicago', 'Houston', 'Phoenix']

Expected Output:

{'Albert': {'age': 23, 'city': 'New York'},
 'John': {'age': 24, 'city': 'Los Angeles'},
 'Peter': {'age': 22, 'city': 'Chicago'},
 'James': {'age': 25, 'city': 'Houston'},
 'Robert': {'age': 23, 'city': 'Phoenix'}}

Solution:

student_name = ['Albert', 'John', 'Peter', 'James', 'Robert']
student_age = [23, 24, 22, 25, 23]
student_city = ['New York', 'Los Angeles', 'Chicago', 'Houston', 'Phoenix']

student_dict = {}

for i in range(len(student_name)):
    student_dict[student_name[i]] = {'age': student_age[i], 'city': student_city[i]}

student_dict

As the expected output is small dictionary, so we use assert_dict_variable_equals_variable() function to assert the solution with the student dictionary.

Assertions:

expected_output = {'Albert': {'age': 23, 'city': 'New York'},
 'John': {'age': 24, 'city': 'Los Angeles'},
 'Peter': {'age': 22, 'city': 'Chicago'},
 'James': {'age': 25, 'city': 'Houston'},
 'Robert': {'age': 23, 'city': 'Phoenix'}}
assert_dict_variable_equals_variable('student_dict', 'expected_output')

# 2. Create a fruits dictionary

Use the fruits_data list to create a dictionary named fruits where the key is the fruit name and the value is a dictionary containing the color and price of the fruit.

Expected Output:

{'apple': {'color': 'red', 'price': 0.99},
 'banana': {'color': 'yellow', 'price': 0.59},
 'orange': {'color': 'orange', 'price': 0.79},
 'grape': {'color': 'purple', 'price': 1.29},
 ...
}

# Try your solution here
fruits = ...

Solution:

fruits = {}
for fruit in fruits_data:
    name = fruit[0]
    color = fruit[1]
    price = fruit[2]
    fruits[name] = {'color': color, 'price': price}

fruits

In the previous activity, we used assert_dict_variable_equals_variable() function to assert the solution with the student dictionary. But here the expected output is large, so we use assert_dict_variable_equals_json() function to assert the solution with the student dictionary.

# save json file
import json
with open('activity_solutions_files/solution_01.json', 'w') as f:
    json.dump(fruits, f)

Assertions:

# new assertions
assert_dict_variable_equals_json('fruits', 'solution_01.json')

# 3. Create a Dictionary of only red color fruits

Store the result in a variable red_fruits.

# Try your solution here
red_fruits = ...

Solution:

red_fruits = {}

for fruit in fruits:
    name = fruit
    if fruits[name]['color'] == 'red':
        red_fruits[name] = fruits[name]
        
red_fruits

Assertions:

expected_red_fruits = {'apple': {'color': 'red', 'price': 0.99},
 'strawberry': {'color': 'red', 'price': 0.69},
 'raspberry': {'color': 'red', 'price': 2.99}}
assert_dict_variable_equals_variable('red_fruits', 'expected_red_fruits')

# 4. Create a Dictionary of only red and blue color fruits

Store the result in a variable red_blue_fruits, here the key is the color and value is the tuple containing two values - color and its price.

# Write your solution here
red_blue_fruits = ...

Solution:

red_blue_fruits = {}

for fruit in fruits:
    name = fruit
    if fruits[name]['color'] == 'red' or fruits[name]['color'] == 'blue':
        red_blue_fruits[name] = tuple(fruits[name].values())
        
red_blue_fruits

{
  'apple': ('red', 0.99),
  'strawberry': ('red', 0.69),
  'raspberry': ('red', 2.99),
  'blueberry': ('blue', 3.99)
}

As we know that when we save tuple in json file, it will be saved as list. So, we use pickle file to save the expected output and then use assert_dict_variable_equals_pickle() function to assert the solution with the student dictionary.

# save in pickle file
import pickle
with open('activity_solutions_files/solution_04.pkl', 'wb') as f:
    pickle.dump(red_blue_fruits, f)

Assertions:

# new assertions
assert_dict_variable_equals_pickle('red_blue_fruits', 'solution_04.pkl')