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Call a function with a random number of arguments

I have a function like that:

def my_function(*args):
    for arg in args:

and I would like to call it with a random number of arguments. Something like:

args = tuple(random.randint(1, 500) for _ in range(10))

And I can't make it work. Any suggestions?



2 Answers

Chris Freeman
Chris Freeman
Treehouse Moderator 67,989 Points

Jacques Plomion, you are correct that my_function is seeing the tuple as a single argument. The power of the asterisk in *args can be used in two ways:

  • as a catchall to receive an arbitrary number of arguments, and
  • to expand a container into individual arguments

The second way is used when you see code like:

    def __init__(*args, **kwargs):  # used here to catch all arguments
        super().__init(*args, **kwargs)  # used here to expand back to individual arguments

So, the simple solution is to call your function as: my_function(*args)

>>> import random
>>> args = tuple(random.randint(1, 500) for _ in range(10))
>>> args
(284, 481, 276, 323, 22, 1, 274, 395, 425, 381)
>>> my_function(args)
(284, 481, 276, 323, 22, 1, 274, 395, 425, 381)
>>> my_function(*args)

Post back if you have more questions. Good Luck!!

Thanks Chris.

Clayton Perszyk
Clayton Perszyk
Treehouse Moderator 48,107 Points

Hey Jacques,

You need to import the random library:

import random

then you can call:

random.randint(n1, n2)


from random import randint

then you can call:

randint(n1, n2)

Hi Clayton,

Thanks for taking the time to respond to me. I guess I didn't explain what I am trying to do well enough so let me try again:

I am trying to call my_function with a random number of arguments in *args. The args would be determined randomly when I run the script. So doing:

args = tuple(random.randint(1, 500) for _ in range(10))

creates a tuple with a random number of arguments and when I call my_function I get this result:

(332, 224, 406, 410, 352, 306, 245, 455, 456, 89)   # for example

I think this is because my tuple is seen as one argument (a tuple) when I would like it to be seen as several integer arguments. I hope it is more clear. And again, thank you for helping with this.