Python 3 – Tutorialspoint

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Python 3

About the Tutorial

Python is a general-purpose interpreted, interactive, object-oriented, and high-level
programming language. It was created by Guido van Rossum during 1985 – 1990. Like
Perl, Python source code is also available under the GNU General Public License (GPL).
Python is named after a TV Show called ‘Monty Python’s Flying Circus’ and not after
Python-the snake.

Python 3.0 was released in 2008. Although this version is supposed to be backward
incompatibles, later on many of its important features have been backported to be
compatible with the version 2.7. This tutorial gives enough understanding on Python 3
version programming language. Please refer to this link for our Python 2 tutorial.

This tutorial is designed for software programmers who want to upgrade their Python skills
to Python 3. This tutorial can also be used to learn Python programming language from
scratch.

Audience

Prerequisites

You should have a basic understanding of Computer Programming terminologies. A basic
understanding of any of the programming languages is a plus.

Execute Python Programs

For most of the examples given in this tutorial you will find Try it option, so just make use
of it and enjoy your learning.

Try the following example using Try it option available at the top right corner of the below
sample code box −

#!/usr/bin/python3

print (“Hello, Python!”)

Copyright & Disclaimer

 Copyright 2016 by Tutorials Point (I) Pvt. Ltd.

All the content and graphics published in this e-book are the property of Tutorials Point (I)
Pvt. Ltd. The user of this e-book is prohibited to reuse, retain, copy, distribute or republish
any contents or a part of contents of this e-book in any manner without written consent
of the publisher.

We strive to update the contents of our website and tutorials as timely and as precisely as
possible, however, the contents may contain inaccuracies or errors. Tutorials Point (I) Pvt.
Ltd. provides no guarantee regarding the accuracy, timeliness or completeness of our
website or its contents including this tutorial. If you discover any errors on our website or
in this tutorial, please notify us at contact@tutorialspoint.com

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Table of Contents

About the Tutorial ………………………………………………………………………………………………………………………….. i
Audience ……………………………………………………………………………………………………………………………………….. i
Prerequisites ………………………………………………………………………………………………………………………………….. i
Execute Python Programs ……………………………………………………………………………………………………………….. i
Copyright & Disclaimer ……………………………………………………………………………………………………………………. i
Table of Contents ………………………………………………………………………………………………………………………….. ii

PYTHON 3 – BASIC TUTORIAL ………………………………………………………………………………………… 1

1. Python 3 – What is New? ………………………………………………………………………………………………………….. 2
The __future__ module ………………………………………………………………………………………………………………….. 2
The print Function …………………………………………………………………………………………………………………………. 2
Reading Input from Keyboard …………………………………………………………………………………………………………. 2
Integer Division ……………………………………………………………………………………………………………………………… 3
Unicode Representation …………………………………………………………………………………………………………………. 3
xrange() Function Removed ……………………………………………………………………………………………………………. 4
raise exceprion ……………………………………………………………………………………………………………………………… 4
Arguments in Exceptions ………………………………………………………………………………………………………………… 4
next() Function and .next() Method …………………………………………………………………………………………………. 4
2to3 Utility ……………………………………………………………………………………………………………………………………. 4

2. Python 3 – Overview ………………………………………………………………………………………………………………… 6
History of Python …………………………………………………………………………………………………………………………… 6
Python Features ……………………………………………………………………………………………………………………………. 7

3. Python 3 – Environment Setup…………………………………………………………………………………………………… 8
Local Environment Setup ………………………………………………………………………………………………………………… 8
Getting Python ……………………………………………………………………………………………………………………………… 8
Setting up PATH …………………………………………………………………………………………………………………………….. 9
Setting Path at Unix/Linux …………………………………………………………………………………………………………….. 10
Setting Path at Windows ………………………………………………………………………………………………………………. 10
Python Environment Variables ………………………………………………………………………………………………………. 10
Running Python …………………………………………………………………………………………………………………………… 11

4. Python 3 – Basic Syntax ………………………………………………………………………………………………………….. 13
First Python Program ……………………………………………………………………………………………………………………. 13
Python Identifiers ………………………………………………………………………………………………………………………… 14
Reserved Words ………………………………………………………………………………………………………………………….. 15
Lines and Indentation …………………………………………………………………………………………………………………… 15
Multi-Line Statements ………………………………………………………………………………………………………………….. 17
Quotation in Python …………………………………………………………………………………………………………………….. 17
Comments in Python ……………………………………………………………………………………………………………………. 17
Using Blank Lines …………………………………………………………………………………………………………………………. 18
Waiting for the User …………………………………………………………………………………………………………………….. 18
Multiple Statements on a Single Line ……………………………………………………………………………………………… 18
Multiple Statement Groups as Suites ……………………………………………………………………………………………… 19
Command Line Arguments ……………………………………………………………………………………………………………. 19

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Parsing Command-Line Arguments ………………………………………………………………………………………………… 20

5. Python 3 – Variable Types ……………………………………………………………………………………………………….. 23
Assigning Values to Variables ………………………………………………………………………………………………………… 23
Multiple Assignment ……………………………………………………………………………………………………………………. 23
Standard Data Types…………………………………………………………………………………………………………………….. 24
Python Numbers ………………………………………………………………………………………………………………………….. 24
Python Strings……………………………………………………………………………………………………………………………… 25
Python Lists ………………………………………………………………………………………………………………………………… 26
Python Tuples ……………………………………………………………………………………………………………………………… 27
Python Dictionary ………………………………………………………………………………………………………………………… 27
Data Type Conversion …………………………………………………………………………………………………………………… 28

6. Python 3 – Basic Operators ……………………………………………………………………………………………………… 30
Types of Operator ………………………………………………………………………………………………………………………… 30
Python Arithmetic Operators ………………………………………………………………………………………………………… 30
Python Comparison Operators ………………………………………………………………………………………………………. 32
Python Assignment Operators ………………………………………………………………………………………………………. 33
Python Bitwise Operators ……………………………………………………………………………………………………………… 35
Python Logical Operators ……………………………………………………………………………………………………………… 37
Python Membership Operators ……………………………………………………………………………………………………… 38
Python Identity Operators …………………………………………………………………………………………………………….. 39
Python Operators Precedence ………………………………………………………………………………………………………. 40

7. Python 3 – Decision Making …………………………………………………………………………………………………….. 43
IF Statement ……………………………………………………………………………………………………………………………….. 44
IF…ELIF…ELSE Statements …………………………………………………………………………………………………………….. 45
Nested IF Statements …………………………………………………………………………………………………………………… 48
Single Statement Suites ………………………………………………………………………………………………………………… 49

8. Python 3 – Loops ……………………………………………………………………………………………………………………. 51
while Loop Statements …………………………………………………………………………………………………………………. 52
for Loop Statements …………………………………………………………………………………………………………………….. 56
Nested loops ……………………………………………………………………………………………………………………………….. 59
Loop Control Statements ………………………………………………………………………………………………………………. 60
break statement ………………………………………………………………………………………………………………………….. 61
continue Statement ……………………………………………………………………………………………………………………… 63
pass Statement ……………………………………………………………………………………………………………………………. 65
Iterator and Generator …………………………………………………………………………………………………………………. 66

9. Python 3 – Numbers ………………………………………………………………………………………………………………. 68
Mathematical Functions ……………………………………………………………………………………………………………….. 70
Number abs() Method ………………………………………………………………………………………………………………….. 71
Number ceil() Method ………………………………………………………………………………………………………………….. 71
Number exp() Method ………………………………………………………………………………………………………………….. 72
Number fabs() Method …………………………………………………………………………………………………………………. 73
Number floor() Method ………………………………………………………………………………………………………………… 74
Number log() Method…………………………………………………………………………………………………………………… 75
Number log10() Method ………………………………………………………………………………………………………………. 76
Number max() Method …………………………………………………………………………………………………………………. 77
Number min() Method …………………………………………………………………………………………………………………. 78
Number modf() Method ……………………………………………………………………………………………………………….. 79

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Number pow() Method ………………………………………………………………………………………………………………… 80
Number round() Method ………………………………………………………………………………………………………………. 80
Number sqrt() Method …………………………………………………………………………………………………………………. 81
Random Number Functions …………………………………………………………………………………………………………… 82
Number choice() Method ……………………………………………………………………………………………………………… 82
Number randrange() Method ………………………………………………………………………………………………………… 83
Number random() Method ……………………………………………………………………………………………………………. 84
Number seed() Method ………………………………………………………………………………………………………………… 85
Number shuffle() Method …………………………………………………………………………………………………………….. 86
Number uniform() Method …………………………………………………………………………………………………………… 87
Trigonometric Functions ………………………………………………………………………………………………………………. 88
Number acos() Method ………………………………………………………………………………………………………………… 88
Number asin() Method …………………………………………………………………………………………………………………. 89
Number atan() Method ………………………………………………………………………………………………………………… 90
Number atan2() Method ………………………………………………………………………………………………………………. 91
Number cos() Method ………………………………………………………………………………………………………………….. 92
Number hypot() Method ………………………………………………………………………………………………………………. 93
Number sin() Method …………………………………………………………………………………………………………………… 94
Number tan() Method ………………………………………………………………………………………………………………….. 95
Number degrees() Method ……………………………………………………………………………………………………………. 96
Number radians() Method …………………………………………………………………………………………………………….. 97
Mathematical Constants ………………………………………………………………………………………………………………. 98

10. Python 3 – Strings ………………………………………………………………………………………………………………….. 99
Accessing Values in Strings ……………………………………………………………………………………………………………. 99
Updating Strings ………………………………………………………………………………………………………………………….. 99
Escape Characters ……………………………………………………………………………………………………………………… 100
String Special Operators ……………………………………………………………………………………………………………… 101
String Formatting Operator …………………………………………………………………………………………………………. 102
Triple Quotes …………………………………………………………………………………………………………………………….. 104
Unicode String …………………………………………………………………………………………………………………………… 105
String capitalize() Method …………………………………………………………………………………………………………… 109
String center() Method ……………………………………………………………………………………………………………….. 110
String count() Method ………………………………………………………………………………………………………………… 111
String decode() Method ……………………………………………………………………………………………………………… 112
String encode() Method ……………………………………………………………………………………………………………… 112
String endswith() Method …………………………………………………………………………………………………………… 113
String expandtabs() Method………………………………………………………………………………………………………… 114
String find() Method …………………………………………………………………………………………………………………… 115
String index() Method ………………………………………………………………………………………………………………… 116
String isalnum() Method ……………………………………………………………………………………………………………… 117
String isalpha() Method ………………………………………………………………………………………………………………. 118
String isdigit() Method ………………………………………………………………………………………………………………… 118
String islower() Method ………………………………………………………………………………………………………………. 119
String isnumeric() Method ………………………………………………………………………………………………………….. 120
String isspace() Method ………………………………………………………………………………………………………………. 121
String istitle() Method ………………………………………………………………………………………………………………… 122
String isupper() Method ……………………………………………………………………………………………………………… 122
String join() Method …………………………………………………………………………………………………………………… 123
String len() Method ……………………………………………………………………………………………………………………. 124
String ljust() Method ………………………………………………………………………………………………………………….. 125
String lower() Method ………………………………………………………………………………………………………………… 125

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String lstrip() Method …………………………………………………………………………………………………………………. 126
String maketrans() Method …………………………………………………………………………………………………………. 127
String max() Method ………………………………………………………………………………………………………………….. 128
String min() Method …………………………………………………………………………………………………………………… 129
String replace() Method ……………………………………………………………………………………………………………… 129
String rfind() Method ………………………………………………………………………………………………………………….. 130
String rindex() Method ……………………………………………………………………………………………………………….. 131
String rjust() Method ………………………………………………………………………………………………………………….. 132
String rstrip() Method …………………………………………………………………………………………………………………. 133
String split() Method ………………………………………………………………………………………………………………….. 134
String splitlines() Method ……………………………………………………………………………………………………………. 135
String startswith() Method ………………………………………………………………………………………………………….. 135
String strip() Method ………………………………………………………………………………………………………………….. 136
String swapcase() Method …………………………………………………………………………………………………………… 137
String title() Method …………………………………………………………………………………………………………………… 138
String translate() Method ……………………………………………………………………………………………………………. 138
String upper() Method ………………………………………………………………………………………………………………… 140
String zfill() Method ……………………………………………………………………………………………………………………. 140
String isdecimal() Method …………………………………………………………………………………………………………… 141

11. Python 3 – Lists ……………………………………………………………………………………………………………………. 143
Python Lists ………………………………………………………………………………………………………………………………. 143
Accessing Values in Lists ……………………………………………………………………………………………………………… 143
Updating Lists ……………………………………………………………………………………………………………………………. 144
Delete List Elements …………………………………………………………………………………………………………………… 144
Basic List Operations ………………………………………………………………………………………………………………….. 144
Indexing, Slicing and Matrixes ……………………………………………………………………………………………………… 145
Built-in List Functions & Methods ………………………………………………………………………………………………… 145
List len() Method ……………………………………………………………………………………………………………………….. 146
List max() Method ……………………………………………………………………………………………………………………… 147
List min() Method ………………………………………………………………………………………………………………………. 147
List list() Method ……………………………………………………………………………………………………………………….. 148
List append() Method …………………………………………………………………………………………………………………. 150
List count() Method ……………………………………………………………………………………………………………………. 151
List extend() Method ………………………………………………………………………………………………………………….. 151
List index() Method ……………………………………………………………………………………………………………………. 152
List insert() Method ……………………………………………………………………………………………………………………. 153
List pop() Method ………………………………………………………………………………………………………………………. 154
List remove() Method …………………………………………………………………………………………………………………. 154
List reverse() Method …………………………………………………………………………………………………………………. 155
List sort() Method ………………………………………………………………………………………………………………………. 156

12. Python 3 – Tuples…………………………………………………………………………………………………………………. 157
Accessing Values in Tuples ………………………………………………………………………………………………………….. 157
Updating Tuples …………………………………………………………………………………………………………………………. 158
Delete Tuple Elements ……………………………………………………………………………………………………………….. 158
Basic Tuples Operations ……………………………………………………………………………………………………………… 159
Indexing, Slicing, and Matrixes …………………………………………………………………………………………………….. 159
No Enclosing Delimiters ………………………………………………………………………………………………………………. 160
Built-in Tuple Functions ………………………………………………………………………………………………………………. 160
Tuple len() Method …………………………………………………………………………………………………………………….. 160
Tuple max() Method …………………………………………………………………………………………………………………… 161

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Tuple min() Method …………………………………………………………………………………………………………………… 162
Tuple tuple() Method …………………………………………………………………………………………………………………. 162

13. Python 3 – Dictionary ………………………………………………………………….