Predefined Modules in python

1. Create a python module called Bank.
2. Add functions: deposit(amount) withdraw(amount)
3. Create one more python module called Customer
4. From customer module, call deposit and withdraw functions of Bank module.

#bank.py
def deposit(amount):
    print("Enter the deposit amount:",amount)
    return(amount)
def withdraw(amount):
    print("Enter the withdraw amount:",amount)
    return(amount)

Create the python module file name is called bank.py
The two functons are
deposit(amount): This function takes one parameter amount and prints the message indicating the deposit amount.
withdraw(amount): This function also takes one parameter amount and prints the message indicating the withdrawal amount.

#customer.py
import bank
bank_deposit=bank.deposit(1000)
bank_withdraw=bank.withdraw(500)
bank_statement=bank_deposit-bank_withdraw
print("Balance amount:",bank_statement)

Create the another python module file name is called customer.py

Using this import keyword we can import the bank module. so we can access the deposit() and withdraw() functions from the customer.py

Enter the deposit amount: 1000
Enter the withdraw amount: 500
Balance amount: 500

Python predefined modules:

1.random:

The random module allows you to generate random numbers, shuffle data, and select random elements from sequences.

import random
otp = random.randint(100000,999999)
print(otp)

random.randint(a, b) returns a random integer between a and b (inclusive).

624367

2.math:

The math module provides functions for basic mathematical operations and constants.

import math
print(math.fabs(-5))

math.fabs(x): Returns the absolute value of x.

5.0

3.os:

Provides functions for interacting with the operating system (e.g., file handling, directories).

import os
print(os.getcwd())  

It will display the currentb working directory.

/home/prigo/Desktop

4.sys

Provides access to system-specific parameters and functions, such as arguments passed to the script.

import sys
print(sys.argv)  

It will display the filename.

['one.py']

5.datetime

Used for manipulating dates and times.

import datetime
now = datetime.datetime.now()
print(now) 

It will display the current date and time.

2024-11-22 00:59:19.436950

7.csv
For reading and writing CSV files.

import csv
with open('data.csv', 'w', newline='') as file:
    writer = csv.writer(file)
    writer.writerow(['Name', 'Age'])
    writer.writerow(['Alice', 25])

8.numpy
A powerful library for numerical operations on arrays and matrices.

import numpy as np
arr = np.array([1, 2, 3, 4])
print(np.mean(arr))  # Mean of the array

9.pandas
Used for data manipulation and analysis, especially for structured data like tables.

import pandas as pd
df = pd.DataFrame({'Name': ['Alice', 'Bob'], 'Age': [25, 30]})
print(df)

10.matplotlib
A popular plotting library for creating static, interactive, and animated visualizations.

import matplotlib.pyplot as plt
plt.plot([1, 2, 3], [4, 5, 6])
plt.show()