Dictionaries

Learning Objectives Define what a dictionary is in Python. Explain the concept of a key-value pair. Create a new dictionary with at least two key-value pairs. Access a value in a dictionary using its key. Add a new key-value pair to an existing dictionary. Update the value of an existing key in a dictionary. Ever wonder how your phone instantly finds a friend's number just by their name? 📱 Dictionaries in Python work in a very similar way! In this lesson, you will learn about a super useful Python data type called a dictionary. Dictionaries let us store connected pieces of information, like a person's name and their age, or a word and its definition. This is a powerful way to organize data in your programs. Real-World Applications Storing user profiles (usern...

TermDefinitionExample DictionaryA collection of items stored in key-value pairs. Dictionaries are created using curly braces {}.student = {'name': 'Leo', 'grade': 6} KeyThe unique identifier for an item in a dictionary. It's like a word in a real dictionary.In {'name': 'Leo'}, the key is 'name'. ValueThe data associated with a key. It's like the definition of a word in a real dictionary.In {'name': 'Leo'}, the value is 'Leo'. Key-Value PairThe combination of a key and its value, separated by a colon (:).In the dictionary {'name': 'Leo', 'grade': 6}, the first key-value pair is 'name': 'Leo'. Curly Braces {}The special symbols used to start a...

Creating a Dictionary variable_name = {key1: value1, key2: value2} To create a dictionary, use curly braces {}. Inside, list your key-value pairs, with a colon : between the key and value, and a comma , separating each pair. Accessing a Value variable_name[key] To get the value for a specific key, use the dictionary's variable name followed by the key inside square brackets []. Adding or Updating a Value variable_name[key] = new_value To add a new item, provide a new key in square brackets and assign it a value. To update an existing item, use its key in square brackets and assign it a new value.