I have a program- main.py
that generates values for a few parameters depending on the user provided inputs. I need to share these variables with other modules- aux.py
. To do that I did the following (simplified code below) -
This the main.py
file:
# these three variables are dynamically calculated depending on the user provided input
a = 12
b = 13
c = 14
def declare_global():
global a, b, c
declare_global()
import aux
aux.print_all()
This is the aux.py
file
def print_all():
a = globals()['a']
b = globals()['b']
c = globals()['c']
print(a)
print(b)
print(b)
Running the main.py
file results in the following error
Traceback (most recent call last): File "/Users/new/Library/Preferences/PyCharmCE2018.3/scratches/global_experiment/main.py", line 13, in aux.print_all() File "/Users/new/Library/Preferences/PyCharmCE2018.3/scratches/global_experiment/aux.py", line 2, in print_all a = globals()['a'] KeyError: 'a'
There is a very similar post addressing the same issue here but the posts there suggest adding all global variables to a new file and then importing the created file. But I cannot do that as I'll have no prior information as to what values these variables will take.
So, how do I share variables across modules?
EDIT
I lost some complexity of the actual program in order to make a minimalistic example. The reason I cannot pass the variables a,b,c
to the print_all
function is because in the actual program, the variables a,b,c
are not serializable. They are spark dataframe objects. And one of the modules I use there (which here I am representing by print_all
) serializes all its inputs I end up with an error (spark dataframes aren't serializable). Using a few workarounds I have arrived here where I use global variables and no inputs to the functions.