out.dot

digraph G {
"ま" -> "い"
"え" -> "か"
"ん" -> "き"
"き" -> "ま"
"え" -> "る"
"い" -> "じ"
"か" -> "き"
"ん" -> "さ"
"じ" -> "ま"
"ん" -> "G"
"じ" -> "ん"
"る" -> "い"
"さ" -> "い"
"S" -> "る"
"ん" -> "じ"
"か" -> "ま"
"じ" -> "か"
"ま" -> "さ"
"ば" -> "ん"
"い" -> "ん"
"る" -> "か"
"い" -> "ば"
"S" -> "い"
"じ" -> "ば"
"き" -> "じ"
"S" -> "き"
"ん" -> "い"
"ま" -> "え"
"さ" -> "じ"
"か" -> "る"
"S" -> "じ"
"ん" -> "ば"
"い" -> "ま"
"る" -> "じ"
"か" -> "ん"
"ん" -> "か"
"S" -> "ま"
"ま" -> "じ"
"S" -> "さ"
"ば" -> "い"
"か" -> "え"
"る" -> "さ"
"き" -> "え"
"S" -> "え"
"き" -> "ん"
"S" -> "か"
"い" -> "き"
"ん" -> "ま"
"さ" -> "ん"
"ま" -> "ん"
"ん" -> "え"
"S" -> "ば"
"ば" -> "る"
"え" -> "ん"
"る" -> "き"
}
/* version: v10.55.26 */

saiban.py

unique_words = frozenset((
    'さいばんいん',
    'さいばんかん',
    'さんばるかん',
    'さんばいまん',
    'さいばいまん',
    'ばんさんかん',
    'ばいきんまん',
    'るいじんえん',
    'ばるさん',
    'かんばん',
    'まいばん',
    'ばんばん',
    'きんえん',
    'ばんきん',
    'えかきまじん',
    'えんばん',
    'さんじかん',
    'えんじん',
    'かんじん',
    'いんさん',
    'かるかん',
    'きえるじかん',
    'かまえるきじまさん',
    'かえん',
    'さじん',
    'じばん',
))

unique_unigrams = frozenset(char for word in unique_words for char in word)
unique_bigrams = frozenset((bigram for bigrams in (zip('S' + word, word + 'G')
                           for word in unique_words) for bigram in bigrams))
graphviz_content = '\n'.join(('"{}" -> "{}"'.format(*bigram)
                             for bigram in unique_bigrams))

TEMPLATE = '''\
digraph G {{
{}
}}
/* version: v{}.{}.{} */
'''

versions = len(unique_unigrams), len(unique_bigrams), len(unique_words)
print(TEMPLATE.format(graphviz_content, *versions))

いちおう Python 3.4 で動作。 2.7 で動くかは試してない。

事の発端: https://twitter.com/yuitest_dev/status/575743269524537344

エスケープ考慮してません。
たとえば """ や改行を含む文字列だとたぶん正しい形式で出力しません。

必要な方は自分で対応してください…・。