how to use @ in python code

 The @ symbol in Python has a few key uses:

1. Decorators:

• This is the most common use.

• Decorators are a powerful way to modify the behavior of functions or classes without directly changing their code.

• They are placed before the function or class definition.

  Python

  def my_decorator(func):
      def wrapper():
          print("Something is happening before the function is called.")
          func()
          print("Something is happening after the function is called.")
      return wrapper
  
  @my_decorator
  def say_hello():
      print("Hello!")
  
  say_hello() 
  

  In this example: - my_decorator is a function that takes another function (func)¹ as an argument. - @my_decorator above say_hello() is equivalent to say_hello = my_decorator(say_hello).

2. Matrix Multiplication:

• In libraries like NumPy, @ is used for matrix multiplication.

  Python

  import numpy as np
  
  a = np.array([[1, 2], [3, 4]])
  b = np.array([[5, 6], [7, 8]])
  
  result = a @ b 
  print(result) 
  

3. String Formatting (f-strings):

• Inside f-strings, @ can be used to access attributes or methods of an object.

  Python

  class MyClass:
      def __init__(self, name):
          self.name = name
  
  obj = MyClass("Example")
  print(f"The object's name is: {@obj.name}") 
  

Remember these key uses of the @ symbol in Python.