I don't know what am I doing wrong here. I am importing the module from the functions package in the tests package. I tried every method but couldn't solve this problem while I tried to run valid_test.py
You need to use one dot before the functions so the python will know it is in the folder "above" the current location (import statement).
This look like this issue.
When specifying what module to import you do not have to specify the absolute name of the module. When a module or package is contained within another package it is possible to make a relative import within the same top package without having to mention the package name. By using leading dots in the specified module or package after from you can specify how high to traverse up the current package hierarchy without specifying exact names. One leading dot means the current package where the module making the import exists. Two dots means up one package level. Three dots is up two levels, etc. So if you execute from . import mod from a module in the pkg package then you will end up importing pkg.mod. If you execute from ..subpkg2 import mod from within pkg.subpkg1 you will import pkg.subpkg2.mod. The specification for relative imports is contained within PEP 328.
There is another way to solve this issue by adding the "father" folder to the sys.path by:
import os
import sys
sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__, '..')))