Function's arguments

Question

hey guys, i have got a little problem with this part of a code: it has to change the default value of an argument of a function
https://code.sololearn.com/cNNkMA0asY22/?ref=app
the commented part doesn't work, instead the code below run correctly
is it an 'elegant' solution? is there a better way to make this code run correctly?

Answer 1

Hello !
The principle of a default parameter is that it won't change and is used when no parameter is provided on function call.
So in your example, set the default parameter to a value in the function definition:
def f(val=2)
then when you call
f() -> val equals 2.
If you need to set val to another value, call the function with a parameter :
f(val=5)
Another comment, global variable are often not recommended. Your f() function should instead return a value. Like this :
def f(val=2):
print(val)
return val
yourval = f()
# This will print 2 and set yourval to 2
yourval = f(5)
# This will print 5 and set yourval to 5

Answer 2

thank you @Burrich , i used this method because i have to call different functions imported from an external file
all these functions refer to an object which change during the program
to avoid re-writing the reference of the object in each functions i tried to use this ploy
the other solution to avoid using global variable could be to creating a class..