Python has a number of built-in libraries that provide many useful functionalities

Python has a number of built-in libraries that provide many useful functionalities. Some of the commonly used built-in libraries are:

• os for interacting with the operating system.
• sys for interacting with the Python interpreter.
• math for mathematical operations.
• random for generating random numbers.
• datetime for working with dates and times.
• json for working with JSON data.
• re for working with regular expressions.
• csv for reading and writing CSV files.

There are many more built-in libraries available in Python, depending on your requirements. You can explore the Python documentation to learn more about the built-in libraries and their functionalities.

os

here’s an example of how to use the Python os library for interacting with the operating system:

import os

# Get the current working directory
cwd = os.getcwd()
print(cwd)

# Create a new directory
os.mkdir('new_directory')

# Rename a file
os.rename('old_file.txt', 'new_file.txt')

# Check if a file exists
if os.path.exists('file.txt'):
  print('The file exists')
else:
  print('The file does not exist')

In this example, we first use the os.getcwd() method to get the current working directory. We then use the os.mkdir() method to create a new directory. We also use the os.rename() method to rename a file and the os.path.exists() method to check if a file exists.

There are many more methods available in the Python os library for interacting with the operating system, such as creating and deleting files and directories, changing file permissions, and more. You can explore the Python documentation to learn more about the os library and its functionalities.

sys

here’s an example of how to use the Python sys library:

import sys

# Get the command line arguments passed to a script
args = sys.argv
print(args)

# Get the Python version
version = sys.version
print(version)

# Exit the program with an error code
sys.exit(1)

In this example, we first use the sys.argv method to get the command line arguments passed to the script. We then use the sys.version method to get the version of Python being used. Finally, we use the sys.exit() method to exit the program with an error code.

There are many more methods available in the Python sys library for interacting with the Python interpreter, such as getting the value of the sys.path variable, setting the maximum recursion depth, and more. You can explore the Python documentation to learn more about the sys library and its functionalities.

json

here’s an example of how to use the Python json library to work with JSON data:

import json

# Define a JSON object
json_object = '{"name": "John", "age": 30, "city": "New York"}'

# Convert a JSON object to a Python dictionary
python_dict = json.loads(json_object)
print(python_dict)

# Define a Python dictionary
python_dict = {'name': 'Jane', 'age': 25, 'city': 'Los Angeles'}

# Convert a Python dictionary to a JSON object
json_object = json.dumps(python_dict)
print(json_object)

In this example, we first use the json.loads() method to convert a JSON object to a Python dictionary. We then use the json.dumps() method to convert a Python dictionary to a JSON object. The json.loads() method is used to parse a JSON formatted string into a Python dictionary, and the json.dumps() method is used to convert a Python dictionary into a JSON formatted string.