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Vittorio Somaschini
33,371 PointsWhy am I not getting a global variable out of this funciton in Python?
Hello everyone.
I would like to know why this code does not print the variable:
def my_function():
output = 'Hello'
return output
my_function()
print (output)
It says output is not defined, so I presume this is not the right method to get a global variable output from that function.
Obviously if I replace the last 2 lines with this:
print(my_function())
I get the string printed, but I need to "generate" global variables that I can reuse
How should I sort this out?
Thanks
Vittorio
PS Kenneth Love as I see you are online ;)
2 Answers
Kenneth Love
Treehouse Guest TeacherSo, global means the variable is available in all scopes. Returning a variable from a function doesn't make that variable available in all scopes (thank goodness!). If you want the output variable's value to be used outside of the function, you need to assign the function call to a variable.
def my_function():
output = 'Hello'
return output
output = my_function()
print(output)
Vittorio Somaschini
33,371 PointsOk Kenneth, thanks.
In fact I had a look at the videos so far when trying to understand this and we haven't used it.
I will try to do it without global variables then.
May I ask why are these discouraged in Python?
ty
Kenneth Love
Treehouse Guest TeacherWe haven't used what? We've used return values a lot, and we'll keep using them. Globals? no, we haven't.
They're discouraged because they're harder to track down and keep in-mind. If I only have to deal with the variables that I've defined and passed into a function, I have less to keep in mind.
Kenneth Love
Treehouse Guest TeacherKenneth Love
Treehouse Guest TeacherAlso, notice I didn't actually tell you how to make a global variable. Globals are pretty heavily discouraged in Python :)