Basics

Overview

This course will teach you the basics and advanced concepts of Python Programming

Prerequisites

What do you need before learning Python?

Computer Literacy
Knowledge of installing a software
A compiler

Python is Easy

To learn Python, you don’t need any prior knowledge of experience on programming.
Python is human readable, making it easier to understand.
Take alook at this example

x = 4
y = 3
summ = x + y
print(summ)

Although we have not taught you how to code in Python yet, you can still easily pick up what the code is doing

What is Python

Python is a programming language.
Python is one of the most popular programming languages

Who created Python?

Python was created by Guido van Rossum and it was first implemented in 1989

What is Python used for?

Python is used for: 1. Web Development 2. Machine Learning 3. Data Science 4. Scripting 5. And many more

What is the latest version of Python?

Python 3 is the latest version of Python
This tutorial is based on the standards of Python 3

Installing Python

Before you can run Python on your PC, you need to install it first.

To install Python in a PC, go to https://www.python.org/downloads/ then download the latest version.

After that, install it just like how you install other apps.

Make sure that you check “Add Python to PATH” for easier installation.

Writing Python Code

In order to learn Python, you need to be able to write and execute code.

Python Console (Shell)

Python console also known as shell allows you to execute Python code line by line

Assuming that you have already installed Python on your PC, you can access the Python console by opening the command prompt and typing python

Let’s start using the console

Type the following and hit enter

name = 'Juma Shafara'

Again, type the following and hit enter

print(name)

After that, you should see this

Juma Shafara

Python Files

Python files are saved with .py file extension

You can use any text editor (even notepad) to create Python files

Just make sure that you save them with the .py extension, forexample hello.py.

Copy this code and save it as hello.py:

print('Hello World!')

To run this Python file on a PC, navigate to the folder where is is located using the command prompt.

Then type the following and hit enter

python hello.py

The console should then output:

Hello World!

Python Displaying output

To display an output in Python, use the print() function.

print('Hello world!')

Hello world!

print(27)

print(3 + 27)

Printing two objects

The print() function can be used to print two objects. Eg.

print('Hello', 'Juma')

Hello Juma

x = 3
y = 7
summ = x + y
print('the sum is ', summ)

the sum is  10

x = 4; y = 3; print(x + y)

Python Statements

A python statement is used to write a value, compute a value, assign a value to a variable, call a functino and many more. Eg.

x = 5
y = 3
summ = x + y
print(summ)

In the example above, we have 4 lines of code. In python, each line typically contains one statement

Multiple statements in one line

You can also write multiple statements in a single of code. Simply separate the statements with semicolons ;

a = 4; b = 3; sum = a + b; print(sum)

Python Syntax

When coding in Python, we follow a syntax. Syntax is the set of rules followed when writing programs

Python indentation

In python, indentation indicates a block(group) of statements
Tabs or leading whitespaces are used to compute the indentation level of a line
It depends on you whether you want to use tabs or whitespaces, in the example below, we use 2 whitespaces

number1 = 4
number2 = 3

if number1 > number2:
  x = 'Hello, world'
  print(x)

Hello, world

Python Comments

Comments in Python are used to clarify or explain codes
Comments are not interpreted by Python, meaning comments will not be executed

# this is a comment
x = 4 
y = 3

# some comment
# second comment
# third comment

print(x + y) # prints out the sum

End of first module

The nice introduction ends here, in the next section, we will look at variables in Python