# Python Decorators

> Learn how Python decorators work: using the @ syntax to wrap a function in another function that can run code before and after it, like a logtime example.

Author: [Flavio Copes](https://flaviocopes.com/about/) | Published: 2021-01-18 | Topics: [Python](https://flaviocopes.com/tags/python/) | Canonical: https://flaviocopes.com/python-decorators/

Decorators are a way to change, enhance or alter in any way how a function works.

Decorators are defined with the `@` symbol followed by the decorator name, just before the function definition.

Example:

```python
@logtime
def hello():
    print('hello!')
```

This `hello` function has the `logtime` decorator assigned.

Whenever we call `hello()`, the decorator is going to be called.

A decorator is a function that takes a function as a parameter, wraps the function in an inner function that performs the job it has to do, and returns that inner function. In other words:

```python
def logtime(func):
    def wrapper():
        # do something before
        val = func()
        # do something after
        return val
    return wrapper
```