def METHOD_NAME():
    # TODO: Check how already existing folder is handled.
    # Arrange
    testfolder = "/dev/shm/testfoldercreation"
    testmode = 0o600
    try:
        shutil.rmtree(testfolder)
    except OSError:
        pass
    # Pre assert to check that this actually does something
    assert not os.path.exists(testfolder)
    # Act
    filesystem_helpers.mkdir(testfolder, testmode)
    # Assert
    assert os.path.exists(testfolder)