import sys
# sys.path is a list of absolute path strings
sys.path.append('/path/to/application/app/folder')
import file
# test.py
import sys
# append current python modules' folder path
# example: need to import module.py present in '/path/to/python/module/not/in/syspath'
sys.path.append('/path/to/python/module/not/in/syspath')
import module
sys.path.insert(1, '/path/to/application/app/folder')
#place the file to be imported, named <imported file>, to the same folder as the python document
#defined function within the <imported file> is <function>
from <imported file> import <function>
#Note that <function> has no parenthesis at the end
from folder import module
OR
import folder.module as module