Modules 1
Modules 1
Modules:
In Python, a module is a file that contains Python code, usually with the purpose of defining functions, classes, or variables that can be reused in other programs.
A module can be created by creating a new Python file with a .py extension and defining the desired functions, classes, and variables within it. For example, suppose we want to create a module called math_utils that contains some basic math functions. We could create a file called math_utils.py with the following code:
def add_numbers(x, y):
return x + y
def subtract_numbers(x, y):
return x - y
def multiply_numbers(x, y):
return x * y
def divide_numbers(x, y):
return x / y
Once the module is defined, it can be imported and used in other Python programs. There are several ways to import a module in Python, but the most common ways are:
- import module_name: This imports the entire module and makes all of its functions, classes, and variables available in the current program. To use a function or variable from the module, you need to prefix it with the module name. For example:
import math_utils
result = math_utils.add_numbers(3, 4)
print(result) # Output: 7
2. from module_name import function_name: This imports a specific function from the module and makes it available in the current program without the need to prefix it with the module name. For example:
from math_utils import add_numbers
result = add_numbers(3, 4)
print(result) # Output: 7
3.from module_name import *: This imports all functions, classes, and variables from the module and makes them available in the current program without the need to prefix them with the module name. However, it’s generally not recommended to use this method because it can lead to naming conflicts and make the code harder to read and understand.
Python comes with a large standard library of modules that provide a wide range of functionality, such as math, file input/output, networking, and more. Additionally, there are many third-party modules available that can be installed using Python’s package manager, pip.
Python has a large standard library of modules that provide a wide range of functionality, such as math, file input/output, networking, and more. These modules can be imported and used in your Python programs. Here are some examples of commonly used modules in Python:
- math: provides mathematical functions such as sine, cosine, square root, and more.
- os: provides a way to interact with the operating system, such as creating and deleting files and directories.
- datetime: provides classes for working with dates and times.
- random: provides functions for generating random numbers.
- json: provides functions for working with JSON data.
To use a module in your Python program, you need to import it. You can import a module using the import statement, followed by the name of the module. Here’s an example:
import math
x = math.sqrt(25)
print(x) # Output: 5.0
This imports the math module and uses the sqrt function to calculate the square root of 25.
You can also import specific functions or classes from a module using the from keyword. Here’s an example:
from datetime import datetime
now = datetime.now()
print(now) # Output: 2023-03-25 15:44:28.954483
This imports the datetime class from the datetime module and uses it to get the current date and time.
In addition to the standard library, there are also many third-party modules available that can be installed using Python’s package manager, pip. These modules can provide additional functionality that is not included in the standard library.