What is the difference between a decorator and a generator in Python?
Alex K
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In Python, decorators and generators are both powerful features that serve different purposes in the language. Let's explore the differences between decorators and generators in more detail: Decorators: - A decorator is a design pattern in Python that allows you to modify the behavior of a function or a class without directly modifying its source code. - Decorators are defined using the@ symbol followed by the decorator function's name, placed immediately before the function or class definition. - Decorators provide a way to add functionality to an existing function or class by wrapping it with another function. - Decorators are commonly used for tasks such as logging, timing, input validation, and memoization. - They enhance the functionality of the decorated function or class, without changing their core implementation. - Decorators are primarily used for enhancing or modifying the behavior of functions or classes at runtime. Here's an example of using a decorator:

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def decorator(func):
    def wrapper(*args, **kwargs):
   # Add additional functionality before calling the original function
   print("Executing decorator")
   return func(*args, **kwargs)
    return wrapper

@decorator
def say_hello():
    print("Hello, World!")

say_hello()  # Output: "Executing decorator" followed by "Hello, World!"

In this example, thedecorator function is defined as a decorator. It takes a function as input and returns a wrapped function (wrapper) that adds additional functionality before calling the original function. The@decorator syntax is used to apply the decorator to thesay_hello function. Whensay_hello() is called, the decorator function is executed first, followed by the execution of the original function. Generators: - A generator is a special type of function that returns an iterator, which can be used to generate a sequence of values on the fly. - Generators are defined using theyield keyword instead ofreturn in the function body. - Generators allow you to iterate over a potentially infinite sequence of values without storing the entire sequence in memory. - They are commonly used for tasks such as generating large data sets, parsing files, and implementing efficient algorithms like Fibonacci series. - Generators provide a memory-efficient way to produce values one at a time, using lazy evaluation. - Generators are primarily used for generating sequences of values, rather than modifying the behavior of existing functions or classes. Here's an example of using a generator:

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def fibonacci():
    a, b = 0, 1
    while True:
   yield a
   a, b = b, a + b

fib_gen = fibonacci()
for i in range(10):
    print(next(fib_gen))

In this example, thefibonacci function is defined as a generator. It uses theyield keyword to return the next value in the Fibonacci sequence each time it is called. The generator is invoked by assigning it to thefib_gen variable. Thenext() function is used to retrieve the next value from the generator in a loop. To summarize, decorators are used to modify the behavior of functions or classes by wrapping them with additional functionality, while generators are used to produce a sequence of values on the fly using lazy evaluation. Decorators are applied using the@ syntax, while generators use theyield keyword to generate values one at a time. Understanding the differences between decorators and generators is important for utilizing their respective capabilities effectively in Python.