def METHOD_NAME(self):
    r'''
    Is true if the Horizontality contains a neighbor tone.
    '''
    if len(self) < 3:
        return False
    elif not all(len(x.pitches) for x in self):
        return False
    pitches = (
        self[0].pitches[0],
        self[1].pitches[0],
        self[2].pitches[0],
    )
    if pitches[0] == pitches[2]:
        if abs(pitches[1].ps - pitches[0].ps) < 3:
            return True
    return False