[Cheat Sheet] Basic Python 3 Syntax Explained with Code and Examples

Basic Python 3 Syntax

Each syntax is explained with Python programming example.

Let’s dive in…

1. Print Statement

print('Hello, world!') #Hello, world!

Printing variable data:

strName = "Chris"
print('My name is', strName) #My name is Chris

2. Comment

Comment is the part of the code which does not get executed.

In programming, it is mainly used for describing the logic of the code and for other purposes.

One line comment:

#this is my first comment

Multi-line comment:

'''
I am new to Python language.
It is an amazing programming language.
You should start learning.
'''

3. Variable Declaration

Python has a dynamic data type. You don’t need to specify the data type of the variable while declaration. The data type of the variable is decided based on the type of data passed to the variable.

Example:

var = 10 #integer variable

var = "Why does everyone love Python?" #string variable

4. String Variable

In programming, the string is the set of characters.

Declaring string variable:

myStr = 'My string'

or

myStr = "This is the string"

Declaring Multi-line string variable:

myStr = ''' String is very useful data structure.
There are many functions available in Python
to manipulate the string variable.'''

4. Arithmetic Operations

varA = 20
varB = 6

#addition
print(varA+varB) #26

#subtraction
print(varA-varB) #14

#multiplication
print(varA*varB) #120

#division
print(varA/varB) #3

#modular
print(varA%varB) #2

Apart from integer, there are various other numeric data types in Python.

5. if-else Statement

if statement:

var = 10
if var>0:
    printf("It is a positive number.")

if-else statement:

var = -10
if var>0:
    printf("It is a positive number.")
else:
    printf("It is not a positive number.")

6. for loop

Loop is used to execute the same lines of code multiple times.

Example: Print the number from 1 to 9.

for i in range(1:10):
    print(i)

Read more about range() method.

7. Definition/Function

There are two parts. First, you have to declare the function. Then call the function to execute the code written inside the function.

def myFirstFunc():
   print("Thanks for calling!")

myFirstFunction() #calling function

8. Taking User Input from Keyboard

You can also take the user input from the keyboard.

strName = input("Enter your good name:")
print(strName)

9. List in Python

The list is somewhat similar to the array in C/C++ programming. It stores multiple values in one variable.

Example: Create employee list which stores the employee-id, name, and salary.

empList = [45, 'Alice', 2560]

print(empList[0]) #45
print(empList[1]) #Alice
print(empList[2]) #2506

#looping over all the elements in the list.
for i in empList:
    print(i)

10. Tuple in Python

The tuple is a little bit different from the list in Python.

Example: Create a Python tuple to store the employee data like employee id, name, salary.

empTup = (45, 'Alice', 2560)

print(empTup(0)) #45
print(empList(1)) #Alice
print(empList(2)) #2506

Read difference between list and tuple in Python.

11. Dictionary in Python

Dictionary variable stores the key-value pair.

Example: Create a dictionary which stores the employee id and his/her name.

empDict = {12: 'Mark', 45: 'Bob'}

#accesing dictionary value from its key
print(empData[12]) #Mark
print(empData[45]) #Bob

You can perform various operations on dictionary. Read detail Python dictionary tutorial.

This is all about basic Python 3 syntax with the code. If you have any doubt or if you have any questions, ask me in the comment.

Happy Pythoning!