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Python Data Structures
course content

Course Content

Python Data Structures

Python Data Structures

1. Mastering Python Lists
Creating Lists in Python: Declaring and Initializing ListsList Indexing in Python: Accessing Elements EfficientlyWorking with Nested Lists in PythonPython List Length: Measuring and Managing List SizeModifying Lists in Python: Updating and Changing ElementsUsing the append() Method: Adding Elements to ListsUsing the insert() Method: Placing Elements at Specific PositionsDeleting Elements in Python Lists: Removing Items SafelyUsing the remove() Method: Deleting Specific Elements from Lists
2. Mastering Python Dictionaries
Creating a Dictionary in Python: Storing Key-Value PairsAccessing Dictionary ValuesAccessing Dictionary KeysAdding Items to a Dictionary: Updating Key-Value PairsUsing the del Keyword: Removing Dictionary EntriesUsing the pop() Method: Deleting Elements with Return ValuesUsing the popitem() Method: Removing the Last Inserted ItemUsing the clear() Method: Emptying a Dictionary Completely
3. Mastering Python Tuples
Creating a Tuple in Python: Defining Immutable Data StructuresAccessing Elements in a Tuple: Indexing TechniqueConcatenating Tuples in Python: Merging Immutable SequencesDeleting Tuples in Python: Removing References to TuplesUpdating Tuples in PythonAdding Items to a Tuple: Alternative Approaches Using ListsCounting Elements in a Tuple: Using the count() MethodFinding Elements in a Tuple: Using the index() Method for Lookup
4. Mastering Python Sets
Creating a Set in Python: Defining Unordered CollectionsUsing the add() Method: Adding Single Elements to a SetUsing the update() Method: Merging Multiple Elements into a SetAccessing Elements in a Set: Iteration and Membership TestingUsing the remove() and discard() MethodsUsing the clear() Method: Removing All Elements from a Set

book
Adding Items to a Dictionary: Updating Key-Value Pairs

Dictionaries are dynamic, meaning you can add, update, or remove items after the dictionary has been created. Let's explore how to add new items to a dictionary.

Start with creating a dictionary called book with some initial details:


              
12

            
book = {"title": "Pride and Prejudice", "author": "Jane Austen", "year": 1813}
print(book)
copy

To make our dictionary more complete, we can add a new key-value pair to it. For example, we might want to add the genre of the book:


              
1234

            
book = {"title": "Pride and Prejudice", "author": "Jane Austen", "year": 1813}

book["genre"] = "Romance"
print(book)
copy

After adding the new key-value pair, the dictionary now includes:

Updating an Existing Key-Value Pair

If you need to update the value of an existing key, you can do so by reassigning a new value to that key. For example, let's assume the book's publication year was corrected to 1815:


              
1234

            
book = {"title": "Pride and Prejudice", "author": "Jane Austen", "year": 1813, "genre": "Romance"}

book["year"] = 1815
print(book)
copy

Note

Single ' ' and double " " quotes in Python are interchangeable and equivalent.

Task

Swipe to start coding

You are given a dictionary authors_books and 2 variables: author_to_add and fitzgeralds_books.

  • Add a new author and their list of books to the authors_books dictionary.
  • The author should be the key, and the list of books should be the value.

Solution

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SectionΒ 2. ChapterΒ 4
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book
Adding Items to a Dictionary: Updating Key-Value Pairs

Dictionaries are dynamic, meaning you can add, update, or remove items after the dictionary has been created. Let's explore how to add new items to a dictionary.

Start with creating a dictionary called book with some initial details:


              
12

            
book = {"title": "Pride and Prejudice", "author": "Jane Austen", "year": 1813}
print(book)
copy

To make our dictionary more complete, we can add a new key-value pair to it. For example, we might want to add the genre of the book:


              
1234

            
book = {"title": "Pride and Prejudice", "author": "Jane Austen", "year": 1813}

book["genre"] = "Romance"
print(book)
copy

After adding the new key-value pair, the dictionary now includes:

Updating an Existing Key-Value Pair

If you need to update the value of an existing key, you can do so by reassigning a new value to that key. For example, let's assume the book's publication year was corrected to 1815:


              
1234

            
book = {"title": "Pride and Prejudice", "author": "Jane Austen", "year": 1813, "genre": "Romance"}

book["year"] = 1815
print(book)
copy

Note

Single ' ' and double " " quotes in Python are interchangeable and equivalent.

Task

Swipe to start coding

You are given a dictionary authors_books and 2 variables: author_to_add and fitzgeralds_books.

  • Add a new author and their list of books to the authors_books dictionary.
  • The author should be the key, and the list of books should be the value.

Solution

Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
Everything was clear?

How can we improve it?

Thanks for your feedback!

SectionΒ 2. ChapterΒ 4
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