import os


class AddFile:
    def __init__(self):
        print('value')

    def Add_file(self, folder):
        for file in os.listdir(folder):
            print(file + '    DONE!')
            if file[-3:] == 'mp3':
                TrackPath = open('TrackPath.txt', 'w')
                TrackPath.write(folder + file)
                TrackPath.close()
                TrackList = open('TrackList.txt', 'w')
                TrackList.write(file[:3])
                TrackList.close()

AddFile.Add_file('C:/Users/Alcat/Downloads/test/')