Python decorator function to calculate time taken by function to run

timer.py

from functools import wraps
import time


def timeit(func):
    """Decorator to calculate time taken by a function to run"""
    @wraps(func)
    def timed(*args, **kw):
        start = time.time()
        result = func(*args, **kw)
        end = time.time()

        format_str = 'function "{f}" took {took:.3f} seconds'
        message = format_str.format(f=func.__name__, took=end - start)

        # Use logger if provided        
        if kw.get('logger') is not None:
            kw.get('logger').info(message)
        else:
            print(message)

        return result
    return timed


@timeit
def sayhi(name):
    print("Hi {}!".format(name))
    time.sleep(1)


sayhi("Aayush")