Cant import variable from one script to another in python

Question

I have two python script

emotion.py

if __name__ == '__main__':

    user=raw_input("Enter your name\n")     

    print("Calling open smile functions.....")

    subprocess.Popen("correlationSvg.py", shell=True)

correlationSvg.py

from emotion import user
import os
import csv

with open('csv/test/'+user+'.csv') as f:
  reader = csv.DictReader(f, delimiter=';')
  rows = list(reader)

i am getting error

ImportError: cannot import name user

why is it so ?

ProfHase85 · Accepted Answer · 2014-03-05T22:29:25.030

1

The variable user is defined inside the if __name__ == '__main__' block. This one is not executed when the import statement is executed.

You can of course define a (script-) global variable

user = ""
if __name__ == '__main__':

    user=raw_input("Enter your name\n")     

    print("Calling open smile functions.....")

    subprocess.Popen("correlationSvg.py", shell=True)

If you would like to get the user while execution, I would either put the line

user=raw_input("Enter your name\n")

into correlation.py or:

in  sympathy.py:

def get_user():
    user=raw_input("Enter your name\n")

and access this function from correlation.py. Just remember: the import statement happens at the time you call the interpreter, while user assignment happpens at runtime.

edited Mar 05 '14 at 22:29

answered Mar 05 '14 at 22:16

ProfHase85

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That doesn't make sense, `if` doesn't have its own scope in Python. – Pandu Mar 05 '14 at 22:21
what if i need the value from local block ?.After doing as above am getting null value as user in correlationSvg.py – san45 Mar 05 '14 at 22:26
The block needs to be executed when the import happens. I edited the answer – ProfHase85 Mar 05 '14 at 22:35

score 1 · Answer 2 · edited May 23 '17 at 12:10

1

Because you are using if __name__ == '__main__'. If file is being imported from another module, __name__ will be set to the module's name. Which means, codes in that indentation will only be processed if you run emotion.py.

For detailed explanation about __name__, you might wanna look here.

edited May 23 '17 at 12:10

Community

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answered Mar 05 '14 at 22:18

Lafexlos

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score 0 · Answer 3 · answered Mar 05 '14 at 22:17

0

You could try this, to force user to be global:

user = ''
if __name__ == '__main__':
    user=raw_input("Enter your name\n")

However... you should really think about what you are doing here. If you don't expect to set user unless this is the main module - what are you expecting to happen when you import it from another module?

Probably, you should be passing this as a parameter to a function, not trying to import it.

answered Mar 05 '14 at 22:17

Corley Brigman

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what if i need the value from local block ?.After doing as above am getting null value as user in correlationSvg.py – san45 Mar 05 '14 at 22:27
like others have said, `__name__` will only be `__main__` if this is the entry module, i.e. `c:\python26\python.exe emotion.py`. that's not what you want. when you import a module, _all_ its code is executed immediately (though usually, that 'code' just declares a function). If you want the user prompt to be done all the time, don't hide it behind a name check, just include it. You could also make it a function that does the user entry and returns the string; you would then just call the function. – Corley Brigman Mar 06 '14 at 05:23

Cant import variable from one script to another in python

3 Answers3