stringOverlap | Python Fiddle

#bor = "TAAATATAATTTAATAGTATAAAAAAAATTAAATCAAATTAATAATAGTTTAAAAAACTGTTTGTATAATATAATATTATTATATATAATATTAAGCAACTACTATGATACTAATGAAGTATAGTGCTATTTTATTAATATGTAGCGTTAATTTATTTTGTTTTCAAAATAAATTAACTACTTCTCGATGGGAATTCCCTAAAGAAGATTTAATTAAAAAAAAAATAAAAATAGGCATAATTTACCATAATTACATAAATTCTATCTTTTACAATGAAAATTATAAATACATTGCCTTTATCGGAATATTGACATCTTATAATGAATGGATTGAAATACAATTTAGCCCCATAAATTTTTTTACTATCCCAACAAATAAAGATTTTATTTCAAATACTTATTTCAATTTAGCTTTCACTATTTACATTACCAAGTATTCAATTTTAACTGATACACTTGCTATAAAATTTTTTATTGGAACCCAAATCGATTTAACTCTGAGAACTACTATATTTACAGGAAAAACAACTCATGCATTTCTCTATCCAATTCTTCCCATAATTACCTTCAAATTTGAAATTGATTTCATACCTAATAACTATAGTATTTACTATAAATTATCGACTTCTTTTAAAGAATTTATCCTTTTAGATCTAGGAA"
test ="MDRYFFLQDATTVAKLLLGNLLIRKIDKEEIVTRIVETEAYMGITDSACHSYGGKITNRTSAMYRIGGYSYVYIIYGMHYMFNVVTADKNNPQAVLIRSVEPISPLLGEKSILTNGPGKLTKFLNIDLTFNKVDLIGNNELFLQRGLNLDFNIVCSKRININYAQESDINKLWRFYIKDNKFVSRR"

print test
print len(test)
#print bor
#print len(bor)

#def get_overlapped_substr(text_input, str_size, overlapsize):
#    return [ text_input[a:a+str_size] for a in range(0,len(text_input), str_size-overlapsize)], str_size, overlapsize

STR_SIZE=30
OVERLAPSIZE = 10
'''

print range(0, len(test), STR_SIZE-OVERLAPSIZE)
for i in range(0, len(test), STR_SIZE-OVERLAPSIZE):
    print test[i:i+STR_SIZE], i, "\t", len(test[i:i+STR_SIZE]),"\t[", i-(STR_SIZE-len(test[i:i+STR_SIZE])), "-", i-(STR_SIZE-len(test[i:i+STR_SIZE]))+STR_SIZE, "]"
    if (len(test[i:i+STR_SIZE]) < STR_SIZE):
        print test[i-(STR_SIZE-len(test[i:i+STR_SIZE])):i+STR_SIZE]
        break

'''

print range(0, len(test), STR_SIZE-OVERLAPSIZE)
for i in range(0, len(test), STR_SIZE-OVERLAPSIZE):
    string = test[i:i+STR_SIZE], i, len(test[i:i+STR_SIZE]),"["+ repr( i-(STR_SIZE-len(test[i:i+STR_SIZE])))+ "-"+ repr( i-(STR_SIZE-len(test[i:i+STR_SIZE]))+STR_SIZE) +"]"
    if (len(test[i:i+STR_SIZE]) < STR_SIZE):
        string = test[i-(STR_SIZE-len(test[i:i+STR_SIZE])):i+STR_SIZE]
       # print string
        break
#    print string
    print string

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