DNA EHHS APCS | Python Fiddle

sample = ['GTA','GGG','CAC']
suspects = {"suspect1" : "ATCGAAAGCACAATCATGCATCGTGCCAGTGTGTTCGTGTCATCTAGGACGGGGCCATAGGATATATAATTCAATTAAGAATACCTTATACTACTGTCCCCTGTGGTTCGAAGGGGAACTATTTCGTGGGGCGAGCCCACACCGTCTCTTCTGCGGAAGACTTAACACGTTAGGGAGGTGGAATAGTTTCGAACGATGGTTATTAATCGTGATAACGGAACGCTGTCTGGAGGATGAGTCTGACGGTGTGTGACTCGATCAGTCACTCGCTATTCGAACTGCGCGAAAGATCCCAGCGCT", "suspect2" : "CCGTAAGACAAATAATTCAATAAAGATGTCGTTTTGCTAGTTTACGTCAAGGTGTCACGCGCCATCTCTGAGCAGGTGGGCCGACGAGACATTATCCCTGGAGTATCAAACCCGTACAAAGGGAACATCCACACTTTGGTGAATCGAAGCGCGGCATCAGGATTTCCTTTTGGATACCTGAAACAAAGCCCATCGTGGTCCTTAGACTTGGCACACTTACACCTGCAGCGCGCGCATGTGGAATTAGAGGCCAAGTTCGATCCCTACACCGACGTACGATGCAACTGTGTGGATGTGACG", "suspect3" : "TCGCATAAGTACAGTAGATCCTCCCCGCGCATCCTATTTATTAAGTTAATTCTACAGCAATACGATCATATGCGGATCCGCAGTGGCCGGTAGACACACCATGCACTTGATTCCGAGGCCTGTCCCGATATATGAACCCAAACTAGAGCGAGGCTGTTGACGTTTGGAGTTGAAAAAATCTATTATACCAATCGGCTTCAACGTGCTCCACGGCAGGCGCCTGACGAGAGGCCCACACCGAGGAAGTAGACTGTTGCACGTTGAGGATAGCGCTAGCTAACAAAGACGCCTGCTACAACA"}
def check_suspect(suspect):
    matches = 0
    for i in range(len(suspect)/3):
        i *= 3
        for j in sample:
            if j == suspect[i:i+3]:
                matches += 1
    print "There were %s matches" % (matches)
    return matches
def is_criminal(dna_sample):
    if check_suspect(dna_sample) >= 3:
        print "yes"
        return True
    else:
        print "no"
        return False
check_suspect(suspects["suspect1"])
check_suspect(suspects["suspect2"])
check_suspect(suspects["suspect3"])
is_criminal(suspects["suspect1"])
is_criminal(suspects["suspect2"])
is_criminal(suspects["suspect3"])

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