Working with nested data

Let us consider the previously described dictionary of dictionaries.

student_data = {
    'A16771125': {'first_name': 'Timothy', 'last_name': 'Mccarthy', 'pa': 93, 'rq': 61, 'lab': 90,
                  'midterm': 95, 'final': 74},
    'A16560701': {'first_name': 'Regina', 'last_name': 'Pierce', 'pa': 51, 'rq': 66,  'lab': 47,
                  'midterm': 97, 'final': 93},
    'A16891123': {'first_name': 'Blaine', 'last_name': 'Simmons', 'pa': 81, 'rq': 73, 'lab': 94,
                  'midterm': 78, 'final': 84},
    'A16600612': {'first_name': 'Clementine', 'last_name': 'Pierce', 'pa': 96, 'rq': 98, 'lab': 88,
                  'midterm': 99, 'final': 92},
    'A16280707': {'first_name': 'Baxter', 'last_name': 'Gonzalez', 'pa': 100, 'rq': 100, 'lab': 94,
                  'midterm': 95, 'final': 97},
    'A16740228': {'first_name': 'Yuhan', 'last_name': 'Wang', 'pa': 98, 'rq': 73, 'lab': 96,
                  'midterm': 84, 'final': 87},
    'A16790513': {'first_name': 'Regina', 'last_name': 'Sanford', 'pa': 88, 'rq': 90, 'lab': 80,
                  'midterm': 93, 'final': 95},
    'A16393543': {'first_name': 'Rohit', 'last_name': 'Singh', 'pa': 98, 'rq': 80, 'lab': 80,
                  'midterm': 83, 'final': 85},
}

Let’s try how we can solve the following questions with the help of what we have learned about dictionaries so far.

Q1. Print the details of the student with the student_id = ‘A16790513’.

There are two ways you solve this problem as shown below:

# Using the given key directly
print(student_data['A16790513'])

# Using the get method
print(student_data.get('A16790513'))

Since student_data is a dictionary we can access the contents by providing the key directly within square brackets or by using the get method of dictionaries. Both the above statements will print the same details as given below:

{'first_name': 'Regina', 'last_name': 'Sanford', 'pa': 88, 'rq': 90, 'lab': 80, 'midterm': 93, 'final': 95}

Q2. Print the marks obtained by the student with the student_id = ‘A16393543’ in the reading quiz

There are two ways you solve this problem as shown below:

# Using the given keys directly
print(student_data['A16393543']['rq'])

# The above is same as doing:
# student_details_dict = student_data['A16393543']
# rq_grade = student_details_dict['rq']
# print(rq_grade)

# Successively using the get method
print(student_data.get('A16393543').get('rq'))

# The above is same as doing:
# student_details_dict = student_data.get('A16393543')
# rq_grade = student_details_dict.get('rq')
# print(rq_grade)

Since student_data is a dictionary we can access the contents by providing the key directly within square brackets as ‘A16393543’ or by using the get method. This will yield a dictionary containing the details of that student. So we in turn again apply the same method to access contents within this inner dictionary. We can either use the key rq directly or we can use the get method.