python decorators

1def our_decorator(func):
2    def function_wrapper(x):
3        print("Before calling " + func.__name__)
4        func(x)
5        print("After calling " + func.__name__)
6    return function_wrapper
7
8@our_decorator
9def foo(x):
10    print("Hi, foo has been called with " + str(x))
11
12foo("Hi")
13

1#Decorator are just function that take function as first
2#parameter and return a function
3def logging(f):
4  def decorator_function(*args, **kwargs):
5    print('executing '+f.__name__)
6    return f(*args, **kwargs)
7  return decorator_function
8#Use it like this
9@logging
10def hello_world():
11  print('Hello World')
12#calling hello_world() prints out:
13#executing hello_world
14#Hello World

1'pass function which we want to decorate in decorator callable object'
2def our_decorator(func):  # func is function to be decorated by decorator
3  
4  def wrapper(x):       # x is parameter which is passed in func
5    if x%2==0:
6      return func(x)
7    else:
8      raise Exception("number should be even")
9  return wrapper
10
11@ our_decorator
12def func(x):         # actual function 
13  print(x,"is even")
14func(2)
15func(1)
16
17' if you do not want to use @'
18func=our_decorator(func)
19func(2)
20
21
22  
23  

1# decorators are user to decorate functions like what to do before/after calling the function
2import time
3
4def delay_decorator(function):
5    def wrapper_function():
6        print("-----------------------I am gonna greet you--------------------------")
7        time.sleep(2)# waits for 2 seconds
8        function()   # calls the function
9        time.sleep(1)# waits for 1 sec
10        print("------------------How do you feel about that greet?-------------------")
11    return wrapper_function
12
13@delay_decorator
14def greet():
15    print("Helllllloooooooooo")
16
17greet()

1# Decorator with arguments
2import functools
3
4# First function takes the wanted number of repetition
5def repeat(num_times):
6    # Second function takes the function
7    def decorator_repeat(func):
8        # Third function, the wrapper executes the function the number of times wanted        
9        # functools decorator to print the true name of the function passed instead of "wrapper"
10        @functools.wraps(func)
11        def wrapper(*args, **kwargs):
12            for _ in range(num_times):
13                result= func(*args, **kwargs)
14            return result
15        return wrapper
16    return decorator_repeat
17
18# Our function using the decorator
19@repeat(num_times= 3)
20def greet(name):
21    print(f"Hello {name}")
22
23greet("thomas")

1# This function take input from user and return
2# list of 0 and 1, zero represents odd number
3# and 1 represents even number
4def deco(func):
5    def wrap(lst):
6        x = [1 if i % 2 == 0 else 0 for i in lst]
7        return x
8        func(lst)
9    return wrap
10
11@deco   
12def display(l):
13    return (l)
14
15a = [int(x) for x in input("Enter number of elements : ").split(",")]
16print(display(a))