Python - Modules, Comments & Pip

 Open the vs code and first install python extension

Let’s write our very first python program.

Create a file called hello.py and paste the below code in it

print(“Hello World”)         => print is a function (more later)

Execute this file (.py file) by typing python hello.py and you will see Hello World printed on the screen.

Modules

A module is a file containing code written by somebody else (usually) which can be imported and used in our programs.

Pip

Pip is a package manager for python. You can use pip to install a module on your system.

E.g. pip install flask (It will install flask module in your system)

Types of modules

There are two types of modules in Python:

Built-in modules – Pre-installed in Python

External modules – Need to install using pip

Some examples of built-in modules are os, abc, etc.

Some examples of external modules are TensorFlow, flask, etc.

Using Python as a Calculator

We can use python as a calculator by typing “python” + TO DO on the terminal. [It opens REPL or read evaluation print loop]

Comments

Comments are used to write something which the programmer does not want to execute.

Comments can be used to mark author name, date, etc.

Types of Comments:

There are two types of comments in python,

Single line comments – Written using # (pound/hash symbol)

Multi-line comments – Written using ‘’’ Comment ‘’’ or “”” Comment “””.

Notes:

1. To print multiple lines in print function, you have to keep the multiple lines within the tripe quote  ''' or """.

print("""Twinkle, twinkle, little star,

How I wonder what you are.

Up above the world so high,

Like a diamond in the sky.

Twinkle, twinkle, little star,

How I wonder what you are!""")

2. How to import one external module and run on vs code:

https://pypi.org/project/playsound/

run pip install playsound

from playsound import playsound

playsound('C:\\Users\\Srinanda\\Desktop\\python\\1. Chapter 1\\play.mp3')

3. Always Use labels in comments

4. How to print the contents of a directory using os module:

import os

print(os.listdir())

or

import os

print(os.listdir('C://Users//Srinanda'))