Module

What is a Module?

A module is a file containing Python code (functions, variables, classes) that you want to use in another program.

You can think of a module as a code library.

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Why use Modules?

• Code reuse
• Easy maintenance
• Better organization of large programs

Creating Your Own Module with Functions

File: Modules.py

def add(a, b):
    return a + b

def sub(a, b):
    return a - b

def mul(a, b):
    return a * b

def div(a, b):
    return a / b

Import the whole module

import Modules

print(Modules.add(5, 10))
print(Modules.sub(50, 10))

Import specific functions

from Modules import div, add, sub

print(div(10, 5))
print(add(50, 25))

a = int(input("Enter a: "))
b = int(input("Enter b: "))
print(sub(a, b))

Import all functions

from Modules import *

print(add(20, 25))
print(sub(5, 10))
print(mul(8, 10))
print(div(7, 10))

Built-in Module: calendar

import calendar

m = int(input("Enter month number: "))
print(f"Month #{m} is: {calendar.month_name[m]}")

Show a single month

import calendar
yy = 2023
mm = 4
print(calendar.month(yy, mm))

Show a full year

import calendar
yy = 2017
print(calendar.calendar(yy))

Built-in Module: datetime

| Code | Description          | Example  |
| ---- | -------------------- | -------- |
| `%A` | Full weekday name    | Monday   |
| `%a` | Short weekday name   | Mon      |
| `%B` | Full month name      | December |
| `%b` | Short month name     | Dec      |
| `%d` | Day of month (01–31) | 09       |
| `%m` | Month (01–12)        | 07       |
| `%Y` | Year (4 digits)      | 2025     |
| `%y` | Year (2 digits)      | 25       |
| `%H` | Hour (00–23)         | 17       |
| `%I` | Hour (01–12)         | 05       |
| `%p` | AM/PM                | PM       |

Get Current Date and Time

import datetime
x = datetime.datetime.now()
print(x.year)           # Current year
print(x.strftime("%A")) # Full weekday name

Custom Date

import datetime
x = datetime.datetime(2018, 6, 1)
print(x.strftime("%B"))  # Full month name

User Input Date

import datetime
a = int(input("Enter the Year: "))
b = int(input("Enter the Month: "))
c = int(input("Enter the Day: "))

x = datetime.datetime(a, b, c)
print("Current Day:", x.strftime("%A"))