def _get_fake_dataset_contents() -> str:
    """
    Build a fake dataset file and write it to a temporary folder.
    The dataset has "measurements" for 3 different channels 0, 8, and 12, with columns for two
    numerical features NUM1, NUM2 and two categorical features CAT1, CAT".
    Labels are attached to channel 12 only.
    """
    return """subject,channel,label,NUM1,NUM2,CAT1,CAT2
    S1,0,,1.0,11.0,False,catA
    S1,8,,1.8,11.8,True,catA
    S1,12,False,1.12,11.12,True,catA
    S2,0,,2.0,22.0,True,catB
    S2,8,,2.8,22.8,True,catB
    S2,12,True,2.12,22.12,False,catB
    S3,0,,3.0,33.0,False,catB
    S3,8,,3.8,33.8,False,catB
    S3,12,True,3.12,33.12,False,catB
    S4,0,,1.0,11.0,False,catA
    S4,8,,1.8,11.8,False,catA
    S4,12,False,1.12,11.12,False,catA
    S5,0,,2.0,22.0,True,catB
    S5,8,,2.8,22.8,True,catB
    S5,12,True,2.12,22.12,True,catB
    S6,0,,3.0,33.0,False,catA
    S6,8,,3.8,33.8,False,catA
    S6,12,True,3.12,33.12,False,catA
    """