Select rows matching a value in a string within a column
<p>In python's pandas, suppose there is a DataFrame in which the values in one of the columns is a string. </p>

<pre><code>df = pd.DataFrame({'State':['California','Oregon','Washington'],\
     'Cities':['Los Angeles, Oakland, San Diego','Portland, Eugene','Seattle, Spokane']})
</code></pre>

<p>How would you select rows matching one value in any of the string within a column? For example, how would return just the rows that have 'Los Angeles' as one of the cities? </p>

<p>My first thought is to loop through each row in the DataFrame, and then use string manipulation ( .split(',') ) to break up each string (this also does not seem efficient with very large datasets). However, I'm not sure where to go from there to actually select that row.</p>