Using python dict imported from file in another python file

Question

I've the same issue as asked by the OP in How to import or include data structures (e.g. a dict) into a Python file from a separate file. However for some reason i'm unable to get it working.

My setup is as follows:

file1.py:

TMP_DATA_FILE = {'a':'val1', 'b':'val2'}

file2.py:

from file1 import TMP_DATA_FILE
var = 'a'
print(TMP_DATA_FILE[var])

When i do this and run the script from cmd line, it says string indices must be integers.

When i do type(TMP_DATA_FILE), i get class 'str'. I tried to convert this to dict to be able to use dict operations, but couldn't get it working.

If i do print(TMP_DATA_FILE.get(var)), since i'm developing using PyCharm, it lists dict operations like get(), keys(), items(), fromkeys() etc, however when i run the program from command line it says 'str' object has no attributes 'get'.

When i do print(TMP_DATA_FILE) it just lists 'val1'. It doesn't list 'a', 'b', 'val2'.

However the same script when run from PyCharm works without any issues. It's just when i run the script from command line as a separate interpreter process it gives those errors.

I'm not sure if it's PyCharm that's causing the errors or if i'm doing anything wrong.

Originally i had only one key:value in the dict variable and it worked, when i added new key:value pair that's when it started giving those errors.

I've also tried using ast.literal_eval & eval, neither of them worked. Not sure where i'm going wrong.

Any help would be highly appreciated.

Thanks.

• Murali: Forgot to mention - file1.py & file2.py are in different folders and i do have __init__.py in both folders. I also tried json options reading from some of the posts, those didn't work either.
• Murali: I've edited my question to change the import statement. This is the current style of import that i've which i forgot to mention while asking the question. Sorry for any confusion.
• Bharadwaj: check my answer once, may be it helps
• Murali: Thanks mescalinum for the tip. That was indeed the problem. I didn't had the right folders in PYTHONPATH. It works now. Thanks everyone for your suggestions.

Answer 1

There are two ways you can access variable TMP_DATA_FILE in file file1.py:

import file1
var = 'a'
print(file1.TMP_DATA_FILE[var])

or:

from file1 import TMP_DATA_FILE
var = 'a'
print(TMP_DATA_FILE[var])

file1.py is in a directory contained in the python search path, or in the same directory as the file importing it.

Check this answer about the python search path.

• BarzanHayati: They could be in subdirectories not a same directory, I tested it.

Answer 2

If you have the packages created in your project, then you have to link the file from the main project.

For example:
If you have a folder Z which contains 2 folders A and B and those 2 files file1.py and file2.py are present in A and B folders, then you have to import it this way

import Z.A.file1
print(file1.TMP_DATA_FILE)

Answer 3

You calling it the wrong way. It should be like this :

print file1.TMP_DATA_FILE[var]

• Murali: I've tried this approach as well and this was my original code. It didn't work. I should've amended the question to reflect the latest code where i'm doing from file1 import dictVariable, and that's why i've dictVariable[var]

Answer 4

Correct variant:

import file1 
var = 'a'
print(file1.TMP_DATA_FILE[var])

or

from file1 import TMP_DATA_FILE
var = 'a'
print(TMP_DATA_FILE[var])

Answer 5

I use following to read constant definitions from other files when there's no conflicting symbols:

from <sub dir>.<other_file> import *