model1 = Model(material='dna', celsius=37,sodium=0.1, magnesium=0.02)
Y1 = Strand('CGTTAACGCAGTGAGGACGGTAGTTTGTCGTTCCATCGCACC', name='Y1')
Y2 = Strand('CGTTAACGGGTGCGATGGAACGACTTTCGACAGGCCTGGTGTAATTTCACCCATGTTAGTCGA', name='Y2')
Y3 = Strand('ATACGGAAAATGGAGATAGGAAGAGTACAATGTCAGCGATAAATTCCGTATACGACACCAGGCCTGTCGATTACTACCGTCCTCACTG', name='Y3')

t1 = Tube({Y1: 1e-8, Y2: 1e-8, Y3:1e-8 },complexes=SetSpec(max_size=4), name='Tube 1')

my_result = tube_analysis(tubes=[t1], model=model1,
    compute=['pfunc', 'pairs', 'mfe', 'sample', 'subopt'])
print(my_result)