What is OOP?

Introduction to Object-Oriented Programming in Python

George Boorman

Curriculum Manager, DataCamp

Stairs

¹ Image source: https://unsplash.com/@tateisimikito

Thinking in sequences

icons of a person in bed followed by a coffee icon followed by a briefcase icon

an assortment of icons representing many activities

$$\Large{\text{Object = data + functionality}}$$

silhouette of a person with a laptop representing a customer

State - an object's data

Behavior - an object's functionality

customer class

customer class branching out to customer objects

Python objects of the same type behave in the same way
lists are a class
- Created with comma-separated values [1, 2, 3, 4, 5]
- Share the same methods, e.g., .append()
Use type() to find the class

type([1, 2, 3, 4, 5])

<class 'list'>

import pandas as pd
df = pd.DataFrame({"a": [1,2,3], 
                   "b": [4,5,6]})

# shape attribute
df.shape

(3, 2)

import pandas as pd
df = pd.DataFrame({"a": [1,2,3], 
                   "b": [4,5,6]})

# head method
df.head()

# Display attributes and methods
dir([1, 2, 3, 4])

['__add__',
 '__class__',
 '__contains__',
 '__delattr__', 
 ...
 'pop',
 'remove',
 'reverse',
 'sort']

# Display attributes and methods
dir(list)

['__add__',
 '__class__',
 '__contains__',
 '__delattr__', 
 ...
 'pop',
 'remove',
 'reverse',
 'sort']

Term	Definition
Class	A blueprint/template used to build objects
Object	A combination of data and functionality; An instance of a class
State	Data associated with an object, assigned through attributes
Behavior	An object's functionality, defined through methods

Introduction to Object-Oriented Programming in Python