Introduction to Python

Course Content

Introduction to Python

Introduction to Python

1. First Acquaintance with Python

The Very First Steps in Python How to Use Comments for Readability Perform Simple Math in Python Handle More Complex Math in Python Bringing Python Fundamentals Together

2. Variables and Types in Python

How to Store Numbers in Python Python Naming Rules for Variables How to Work with Variables in Python Data Types in Python Challenge: Converting Kilometers to Miles Store Text with Strings in Python String Indexing in Python String Slicing in Python Challenge: Retrieving Letters from String String Concatenation in Python

3. Conditional Statements in Python

Boolean Data Type in Python Challenge: Working with Comparison Operators How to Combine Conditions in Python Challenge: Working with Logical Operators Membership Operators and Type Comparisons in Python How to Use if/else Expressions in Python Challenge: Running a Grocery Store Challenge: Creating Odd and Even Logic if/elif/else Expressions Challenge: Running Grocery Store Extended Challenge: Weather Adviser

4. Other Data Types in Python

Python Lists Common List Methods in Python Challenge: Updating List Nested Lists in Python Challenge: Retrieving Information from Nested List Python Tuples Common Tuple Methods in Python Challenge: Updating Tuple Nested Tuples in Python Challenge: Retrieving Information from Nested Tuple Python Dictionaries Challenge: Creating Dictionary Common Dictionary Methods in Python Challenge: Updating Dictionary

5. Loops in Python

Explore the while Loop in Python Challenge: Working with the While Loop Explore the for Loop in Python Challenge: Working with the For Loop Range Function in Python Challenge: Using the Range Function How to Iterate Over Indexes in Python Explore Nested Loops in Python

6. Functions in Python

Built-in Functions in Python Challenge: Converting Heights How to Create Functions in Python Challenge: Writing First Function Use of if/else Statements in Python Functions Challenge: Identifying Positive Values Functions Without Return in Python Challenge: Creating Logging Function Modifying Functions in Python Challenge: Updating Logic of the Function Lambda Functions in Python Challenge: Creating Lambda Function

Nested Lists in Python

Lists in Python can store different data types, including other lists. Unlike many languages, Python allows nested lists of varying lengths.

For example, when storing countries and their areas, it's more organized to use a separate list for each country instead of a single combined list.


              12345
            
# Two-dimensional list
countries_2d = [["USA", 9629091], ["Canada", 9984670], ["Germany", 357114]]

# Printing nested list
print(countries_2d)

Each country has its own list nested within the main list. But how do we navigate this structure?

In a two-dimensional list, each element is itself a list, and we access inner items using indexing.

For example, in a countries_2d list with 3 sublists (each containing 2 items):

countries_2d[1] retrieves the second sublist (Python indexing starts at 0).
countries_2d[1][0] fetches the first item of that sublist.


              123456
            
# Two-dimensional list
countries_2d = [['USA', 9629091], ['Canada', 9984670], ['Germany', 357114]]

# Pull elements
print(countries_2d[1])
print(countries_2d[1][0])

Everything was clear?

Thanks for your feedback!

Section 4. Chapter 4

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