Is there a faster way to check if a value is in a set in python?
<p>I want to maintain a list of strings and keep checking for different variables if they are in the list.</p>

<p>What I'm doing is :</p>

<pre><code>li=[one,two,three]
for x in different_x_values:
  if(x in li):
    print 'yes'
</code></pre>

<p>Is there a faster way than using <code>x in li</code> that checks if a some string is in some other collection of strings?</p>
