Modules, Comments & Pip

 Modules, Comments & Pip

Let’s write our very first python program.

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

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

Copy

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:

1.     Built-in modules – Pre-installed in Python

2.     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 the author's name, date, etc.

Types of Comments:

There are two types of comments in python,

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

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

Chapter 1 – Practice Set

1.     Write a program to print Twinkle-Twinkle Little Star poem in python.

2.     Use REPL and print the table of 5 using it.

3.     Install an external module and use it to perform an operation of your interest.

4.     Write a python program to print the contents of a directory using os module. Search online for the function which does that.

5.     Label the program written in problem 4 with comments.