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COMPUTER SOFTWARE APPLICATION - CITS

Lists are one of 4 built-in data types in Python used to store collections of data, the other 3 are Tuple, Set, and
Dictionary, all with different qualities and usage.
Lists are created using square brackets:

Example
Create a List:
thislist = [“apple”, “banana”, “cherry”]
print(thislist)

OUTPUT
[‘apple’, ‘banana’, ‘cherry’]

List Items
List items are ordered, changeable, and allow duplicate values.
List items are indexed, the first item has index [0], the second item has index [1] etc.

Ordered
When we say that lists are ordered, it means that the items have a defined order, and that order will not change.
If you add new items to a list, the new items will be placed at the end of the list.
Note: There are some list methods that will change the order, but in general: the order of the items will not change.

Changeable
The list is changeable, meaning that we can change, add, and remove items in a list after it has been created.

Allow Duplicates
Since lists are indexed, lists can have items with the same value:
Example
Lists allow duplicate values:

thislist = [“apple”, “banana”, “cherry”, “apple”, “cherry”]
print(thislist)
OUTPUT
[‘apple’, ‘banana’, ‘cherry’, ‘apple’, ‘cherry’]

Python Tuples

Tuples are used to store multiple items in a single variable.
Tuple is one of 4 built-in data types in Python used to store collections of data, the other 3 are List, Set, and
Dictionary, all with different qualities and usage.
A tuple is a collection which is ordered and unchangeable.
Tuples are written with round brackets.
Example: Get your own Python Server
Create a Tuple:

thistuple = (“apple”, “banana”, “cherry”)
print(thistuple)

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CITS : IT&ITES - Computer Software Application - Lesson 120 - 137