# [SOLVED] How to deal with sometimes unused arguments of function?

## Issue

Could you please advise me how to deal with sometimes unused arguments of function? Thank you in advance!

Function:

``````def foo(a, b=2, c="default"):
print(c)
return a + b
``````

Usage:

``````arg_1 = int(input())
if arg_1 == 2:
arg_2 = 3
arg_3 = "using 3"
else:
# what can I do here?
arg_2 = *universal_value_that_is_disabling_argument
arg_3 = *universal_value_that_is_disabling_argument
# I know that I can use arg_2 = 2 and arg_3 = "default",
# but it is not really convenient when there are many arguments

foo(arg_1, b=arg_2, c=arg_3)
``````

I understand that I can do something like this, but it is not really convenient when there are many arguments:

``````arg_1 = int(input())
if arg_1 == 2:
foo(arg_1, 3, "using 3")
else:
foo(arg_1)
``````

## Solution

Call it by unpacking a dictionary for the named arguments. Then you can simply omit the arguments that should get the default.

``````if arg_1 == 2:
options = {'b': 3, 'c': 'using 3'}
else:
options = {}

foo(arg_1, **options)
``````