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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def model_length(gene, domain):
 """ get length of model """

    if gene == '16S':
        domain2max = {'E_coli_K12': int(1538), 'bacteria': int(1689), 'archaea': int(1563), 'eukarya': int(2652)}
        return domain2max[domain]
    elif gene == '23S':
        domain2max = {'E_coli_K12': int(2903), 'bacteria': int(3146), 'archaea': int(3774), 'eukarya': int(9079)}
        return domain2max[domain]
    else:
        print(sys.stderr, '# length unknown for gene: %s, domain: %s' % (gene, domain))
        exit()