checking if a letter is present in a string in python
<p>How can I check if the letter "N" is present in a string.
Example:</p>

<pre><code>flag = False
if string contains N:
   flag = True
</code></pre>

<p>So <code>flag = True</code> if string is <code>"CNDDDNTD"</code> and <code>flag = False</code> if string is <code>"CCGGTTT"</code>. I think re.search will work, but not sure of the options to use.</p>