You’re given two words, <code>begin_word</code> and <code>end_word</code> which are elements of <code>word_list</code>.

Write a function <code>shortest_transformation</code> to find the length of the shortest transformation sequence from <code>begin_word</code> to <code>end_word</code> through the elements of <code>word_list</code>.

Note: Only one letter can be changed at a time and each transformed word in the list must exist inside of <code>word_list</code>.

Note: In all test cases, a path does exist between <code>begin_word</code> and <code>end_word</code>

Example:

Input:

<pre tabindex="0" class="chroma"><code>Input:
begin_word = &#34;same&#34;,
end_word = &#34;cost&#34;,
word_list = [&#34;same&#34;,&#34;came&#34;,&#34;case&#34;,&#34;cast&#34;,&#34;lost&#34;,&#34;last&#34;,&#34;cost&#34;]
</code></pre>

Output:

<pre tabindex="0" class="chroma"><code>def shortest_transformation(begin_word, end_word, word_list) -&gt; 5
</code></pre>

Since the transformation sequence would be:

<pre tabindex="0" class="chroma"><code>&#39;same&#39; -&gt; &#39;came&#39; -&gt; &#39;case&#39; -&gt; &#39;cast&#39; -&gt; &#39;cost&#39;
</code></pre>

which is five elements long.

Write a function to find the length of the shortest transformation sequence from begin_word to end_word through the elements of word_list.

Shortest Transformation

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