Quick recap: last time we stored single values in variables. Today's question — what if you want one variable to hold a whole set of values, like five numbers or a row of images?

That's a list (also called an array). We'll build a micro:bit project in Python that creates a list, reads and changes items in it, adds and removes items, and finally uses lists of images to make LED light patterns. We'll predict first, then build, run and fix as we go.

Before anyone runs anything, look at what we're about to build and commit to a prediction. When a list holds five numbers and we ask the micro:bit to show the item at position 0, which number do you think appears first? What do you expect to see after we change or remove an item?

Say your prediction to your partner so we can check it later.

In this lesson, you'll learn the basics of working with arrays in MicroPython. You'll create a simple list, retrieve elements from the list, change elements, add new elements, and remove elements from the list. By the end of this lesson, you'll have a solid understanding of how to work with arrays in MicroPython.

To get started, open the micro:bit Python editor at https://python.microbit.org and create a new project.

Python Microbit: How to create a new project

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To create a new Python project for a Microbit, open the website python.microbit.org.

This will open the code editor with a new project. It might have some example code already added such as:

# Imports go at the top
from microbit import *

# Code in a 'while True:' loop repeats forever
while True:
    display.show(Image.HEART)
    sleep(1000)
    display.scroll('Hello')

You should delete this code except for the import line that you will need. This imports the necessary libraries you will need to code a microbit.

# Imports go at the top
from microbit import *

An array is a collection of items, like numbers or strings, stored in a single variable. In MicroPython, arrays are often called lists. They are useful when you want to store and manipulate multiple values using a single variable.

In this lesson, we'll use the terms 'array' and 'list' interchangeably.

Lists can store different types of data, such as integers, strings, or even other lists. For example:

• Integer List: [1, 2, 3, 4, 5]
• String List: ['apple', 'banana', 'cherry']
• Mixed List: [1, 'apple', 3.14]

Now, let's create a list called 'numbers' with five elements. The elements are the integers from 1 to 5. Add the following code to your editor:

from microbit import *

numbers = [1, 2, 3, 4, 5]