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Python Data Structures
course content

Course Content

Python Data Structures

Python Data Structures

1. List
Creating a ListList IndexingNested ListList LengthModifying a ListThe append() MethodThe insert() MethodDeleting ElementsThe remove() MethodList ComprehensionsList Comprehansions with Conditions
2. Dictionary
Creating a DictionaryAccessing Dictionary ValuesAccessing Dictionary KeysAdding ItemsChallenge: Expand the DictionaryThe del KeywordThe pop() MethodThe popitem() MethodThe clear() MethodDictionary ComprehensionsDictionary Comprehension with Condition
3. Tuple
Creating a Tuple Accessing Elements in a TupleConcatenating TuplesDeleting a TupleUpdating a TupleAdding Items to a TupleCounting Elements in a TupleFinding Elements in a Tuple
4. Set
Creating a SetThe add() MethodThe update() MethodAccessing the Elements of a SetThe remove() and discard() MethodsThe clear() Method

bookList Comprehensions

List comprehensions are a powerful way to create new lists by combining loops and optional conditions into a single, concise statement. They provide a more Pythonic way to perform operations on lists, making your code cleaner and easier to read.

Creating a New List: Traditional for Loop vs. List Comprehension

Let's start with a simple example. You have a travel_wishlist containing cities you want to visit, each represented as a nested list with its name, country, and trip cost.

So, you need a list with city names only, without countries and trip costs.

For that task you can use for loop:


              
12345678910111213

            
travel_wishlist = [
    ["Paris", "France", 2000],
    ["Tokyo", "Japan", 3000],
    ["New York", "USA", 2500],
    ["Kyoto", "Japan", 1500],
    ["Sydney", "Australia", 4000]
]

city_names = []  # a new empty list
for city in travel_wishlist:
    city_names.append(city[0])

print(city_names)  # Output: ['Paris', 'Tokyo', 'New York', 'Kyoto', 'Sydney']
copy

Here, the list comprehension does the same job in a single line, making it concise and readable.


              
1234567891011

            
travel_wishlist = [
    ["Paris", "France", 2000],
    ["Tokyo", "Japan", 3000],
    ["New York", "USA", 2500],
    ["Kyoto", "Japan", 1500],
    ["Sydney", "Australia", 4000]
]

city_names = [city[0] for city in travel_wishlist]

print(city_names)  # Output: ['Paris', 'Tokyo', 'New York', 'Kyoto', 'Sydney']
copy

The list comprehension combines the loop and the condition into a single line, making the code easier to understand at a glance.

Task
test

Swipe to show code editor

You are managing a travel wishlist, and you need to create a new list that contains only the trip costs (the third element) from each destination in the wishlist.

Note

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!

Section 1. Chapter 10
toggle bottom row

bookList Comprehensions

List comprehensions are a powerful way to create new lists by combining loops and optional conditions into a single, concise statement. They provide a more Pythonic way to perform operations on lists, making your code cleaner and easier to read.

Creating a New List: Traditional for Loop vs. List Comprehension

Let's start with a simple example. You have a travel_wishlist containing cities you want to visit, each represented as a nested list with its name, country, and trip cost.

So, you need a list with city names only, without countries and trip costs.

For that task you can use for loop:


              
12345678910111213

            
travel_wishlist = [
    ["Paris", "France", 2000],
    ["Tokyo", "Japan", 3000],
    ["New York", "USA", 2500],
    ["Kyoto", "Japan", 1500],
    ["Sydney", "Australia", 4000]
]

city_names = []  # a new empty list
for city in travel_wishlist:
    city_names.append(city[0])

print(city_names)  # Output: ['Paris', 'Tokyo', 'New York', 'Kyoto', 'Sydney']
copy

Here, the list comprehension does the same job in a single line, making it concise and readable.


              
1234567891011

            
travel_wishlist = [
    ["Paris", "France", 2000],
    ["Tokyo", "Japan", 3000],
    ["New York", "USA", 2500],
    ["Kyoto", "Japan", 1500],
    ["Sydney", "Australia", 4000]
]

city_names = [city[0] for city in travel_wishlist]

print(city_names)  # Output: ['Paris', 'Tokyo', 'New York', 'Kyoto', 'Sydney']
copy

The list comprehension combines the loop and the condition into a single line, making the code easier to understand at a glance.

Task
test

Swipe to show code editor

You are managing a travel wishlist, and you need to create a new list that contains only the trip costs (the third element) from each destination in the wishlist.

Note

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!

Section 1. Chapter 10
toggle bottom row

bookList Comprehensions

List comprehensions are a powerful way to create new lists by combining loops and optional conditions into a single, concise statement. They provide a more Pythonic way to perform operations on lists, making your code cleaner and easier to read.

Creating a New List: Traditional for Loop vs. List Comprehension

Let's start with a simple example. You have a travel_wishlist containing cities you want to visit, each represented as a nested list with its name, country, and trip cost.

So, you need a list with city names only, without countries and trip costs.

For that task you can use for loop:


              
12345678910111213

            
travel_wishlist = [
    ["Paris", "France", 2000],
    ["Tokyo", "Japan", 3000],
    ["New York", "USA", 2500],
    ["Kyoto", "Japan", 1500],
    ["Sydney", "Australia", 4000]
]

city_names = []  # a new empty list
for city in travel_wishlist:
    city_names.append(city[0])

print(city_names)  # Output: ['Paris', 'Tokyo', 'New York', 'Kyoto', 'Sydney']
copy

Here, the list comprehension does the same job in a single line, making it concise and readable.


              
1234567891011

            
travel_wishlist = [
    ["Paris", "France", 2000],
    ["Tokyo", "Japan", 3000],
    ["New York", "USA", 2500],
    ["Kyoto", "Japan", 1500],
    ["Sydney", "Australia", 4000]
]

city_names = [city[0] for city in travel_wishlist]

print(city_names)  # Output: ['Paris', 'Tokyo', 'New York', 'Kyoto', 'Sydney']
copy

The list comprehension combines the loop and the condition into a single line, making the code easier to understand at a glance.

Task
test

Swipe to show code editor

You are managing a travel wishlist, and you need to create a new list that contains only the trip costs (the third element) from each destination in the wishlist.

Note

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!

List comprehensions are a powerful way to create new lists by combining loops and optional conditions into a single, concise statement. They provide a more Pythonic way to perform operations on lists, making your code cleaner and easier to read.

Creating a New List: Traditional for Loop vs. List Comprehension

Let's start with a simple example. You have a travel_wishlist containing cities you want to visit, each represented as a nested list with its name, country, and trip cost.

So, you need a list with city names only, without countries and trip costs.

For that task you can use for loop:


              
12345678910111213

            
travel_wishlist = [
    ["Paris", "France", 2000],
    ["Tokyo", "Japan", 3000],
    ["New York", "USA", 2500],
    ["Kyoto", "Japan", 1500],
    ["Sydney", "Australia", 4000]
]

city_names = []  # a new empty list
for city in travel_wishlist:
    city_names.append(city[0])

print(city_names)  # Output: ['Paris', 'Tokyo', 'New York', 'Kyoto', 'Sydney']
copy

Here, the list comprehension does the same job in a single line, making it concise and readable.


              
1234567891011

            
travel_wishlist = [
    ["Paris", "France", 2000],
    ["Tokyo", "Japan", 3000],
    ["New York", "USA", 2500],
    ["Kyoto", "Japan", 1500],
    ["Sydney", "Australia", 4000]
]

city_names = [city[0] for city in travel_wishlist]

print(city_names)  # Output: ['Paris', 'Tokyo', 'New York', 'Kyoto', 'Sydney']
copy

The list comprehension combines the loop and the condition into a single line, making the code easier to understand at a glance.

Task
test

Swipe to show code editor

You are managing a travel wishlist, and you need to create a new list that contains only the trip costs (the third element) from each destination in the wishlist.

Note

Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
Section 1. Chapter 10
Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
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