[python] os.path.dirname(__file__) returns empty

I want to get the path of the current directory under which a .py file is executed.

For example a simple file D:\test.py with code:

import os

print os.getcwd()
print os.path.basename(__file__)
print os.path.abspath(__file__)
print os.path.dirname(__file__)

It is weird that the output is:

D:\
test.py
D:\test.py
EMPTY

I am expecting the same results from the getcwd() and path.dirname().

Given os.path.abspath = os.path.dirname + os.path.basename, why

os.path.dirname(__file__)

returns empty?

os.path.split(os.path.realpath(__file__))[0]

os.path.realpath(__file__)return the abspath of the current script; os.path.split(abspath)[0] return the current dir

can be used also like that:

dirname(dirname(abspath(__file__)))

import os.path

dirname = os.path.dirname(__file__) or '.'

print(os.path.join(os.path.dirname(__file__))) 

You can also use this way