Pygame load

[Kangen]

Hello
I'm relatively new to Python. Whilst writing an mp3 player I encounter an error.

I have in a previous step created a simple textfile with paths to mp3 files. After reading the file I use a for loop

pygame.mixer.init()
for i, line in enumerate(f):
    if i == 0:
        print(line)
        path, filename = os.path.split(line)

So far nothing strange
For testing purposes I also write variable line (full path to mp3 file) as well as variable path and filename after the split.
And change the working directory

        print('Path: ' + path)
        print('Filename: ' + filename)
        os.chdir(path)

No to call the player (pygame) I use filename in the load() function and then play

        pygame.mixer.music.load(filename)
        pygame.mixer.music.play()

Getting the error pygame.error: "Couldn't open '01-som_vatten.mp3"
If I instead directly write

pygame.mixer.music.load('01-som_vatten.mp3')

It works fine.

Output of the prints are:
Path: C:\temp\ett\tva
Filename: 01-som_vatten.mp3

I cannot work out what is the difference between writing the mp3 filename directly and using a variable. Could it be the wrong variable typ?

Regards
Johan