Creating a Dictionary

Part of the Logic & Flow section of Coddy's Python journey — lesson 8 of 78.

To create a dictionary in Python, you use curly braces {} and specify the key-value pairs within them. Each key-value pair is written as key: value, and multiple pairs are separated by commas.

Here's how you can create a dictionary:

# Creating a dictionary of country capitals
country_capitals = {
    "USA": "Washington, D.C.",
    "France": "Paris",
    "Japan": "Tokyo"
}

# Creating a dictionary of employee information
employee = {
    "name": "John Doe",
    "age": 30,
    "position": "Software Engineer"
}

# Creating an empty dictionary
empty_dict = {}

In the first example, country_capitals is a dictionary with country names as keys and their capitals as values. In the second example, employee is a dictionary containing information about an employee. The third example shows how to create an empty dictionary, which can be useful when you want to add items to it later.

Challenge

Easy

Create a function named create_student_dict that takes three parameters: name, age, and major. The function should return a dictionary where the keys are "name", "age", and "major", and the values are the corresponding values passed to the function.

For example, calling create_student_dict("Alice", 20, "Computer Science") should return a dictionary with the following key-value pairs:

Key: "name", Value: "Alice"
Key: "age", Value: 20
Key: "major", Value: "Computer Science"

Cheat sheet

To create a dictionary in Python, use curly braces {} with key-value pairs separated by commas:

# Dictionary with key-value pairs
country_capitals = {
    "USA": "Washington, D.C.",
    "France": "Paris",
    "Japan": "Tokyo"
}

# Dictionary with different data types
employee = {
    "name": "John Doe",
    "age": 30,
    "position": "Software Engineer"
}

# Empty dictionary
empty_dict = {}

Each key-value pair is written as key: value, where keys are typically strings and values can be any data type.

Try it yourself

def create_student_dict(name, age, major):
    # Write code here

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Logic & Flow

1Variables Exploration

Constants Multiple Variable Assignments Swapping Variables Placeholder Variables Round Numbers List Casting

4Contact Book Application

Display Menu Add Contact

7Sets Part 2

Mathematical Operations Part 1 Mathematical Operations Part 2 Recap - Treasure Hunt Subsets and Supersets Iterating Over Sets Recap - Tournament Tracker

10Basic List Comprehensions

The Syntax Creating Simple Lists Adding Conditions Using Data Aggregation Recap - House Of Lists Recap - Elements Of Freedom

13Inventory Management System

Project Overview Add Item

Update Stock

Check Availability

Generate Report

2Dictionaries Part 1

What is a Dictionary?Creating a DictionaryAccessing Values Modifying Dictionaries Recap - Recipe Manager

5Advanced Decision Making

Ternary Operator Membership Checks Identity Checks Indentation Errors Recap - Vacation Filter

8Student Records Manager

Project Overview Add Student

11Advanced Functions

Returning Multiple Values Lambda Functions Part 1 Lambda Functions Part 2 Recap Challenge - Lambda Sort Recursive Functions Part 1 Recursive Functions Part 2 Recap - Sum Nested List

14Higher-Order Functions

The Map Function The Filter Function Recap - Email Validator Recap - Number Processor

3Dictionaries Part 2

Dictionary Methods Nested Dictionaries Checking for Keys Looping Through Dictionaries Recap - Frequency Counter

6Sets Part 1

What is a Set?Basic Operations Set Methods Recap - Remove Duplicates

9Advanced Data Aggregation

Using Sum Finding Minimum and Maximum Sorting Data Efficiently Recap - Dictionary Sorter

12Basic Error Handling

What is Error Handling?The Try and Except Block Handling Multiple Exceptions Recap - Shopping Cart Errors

15Final Challenges

Smart Contact Manager Word Analytics Data Transformer