How can I make a time delay in Python? [duplicate]

Answer 1

If you would like to put a time delay in a Python script:

Use time.sleep or Event().wait like this:

from threading import Event
from time import sleep

delay_in_sec = 2

# Use time.sleep like this
sleep(delay_in_sec)         # Returns None
print(f'slept for {delay_in_sec} seconds')

# Or use Event().wait like this
Event().wait(delay_in_sec)  # Returns False
print(f'waited for {delay_in_sec} seconds')

However, if you want to delay the execution of a function do this:

Use threading.Timer like this:

from threading import Timer

delay_in_sec = 2

def hello(delay_in_sec):
    print(f'function called after {delay_in_sec} seconds')

t = Timer(delay_in_sec, hello, [delay_in_sec])  # Hello function will be called 2 seconds later with [delay_in_sec] as the *args parameter
t.start()  # Returns None
print("Started")

Outputs:

Started
function called after 2 seconds

Why use the later approach?

• It does not stop execution of the whole script (except for the function you pass it).
• After starting the timer you can also stop it by doing timer_obj.cancel().