title: How to make a new list of specific sequences from another list?
body: <p>I was wondering how I can make a list of pulled specific sequence values (the first three) following a common sequence, to place onto another list. This is more conceptual based versus an actual application if that makes sense. This is an example of what I am trying to accomplish,</p>
  <pre><code>seq = 'ATTACGA'
  og_list = ['ATGGGCATAGA', 'GCCTGAACTT', 'GAATTACGAAGAGT', 'AAGTCCAAT', 'GCACATTACGATAG']
  </code></pre>
  <p>It would ideally pull the remaining sequence from the common sequence stored in the <code>seq</code> variable to get:</p>
  <pre><code>['AGA', 'TAG']
  </code></pre>
  <p>This is because these values are the three after the <code>seq</code> common sequence value. I would imagine the <code>find</code> (<code>.find()</code>) function could be used, but as I am new to Python, if someone can help me figure this out that would be great.</p>
  <p>Here is what I have so far:</p>
  <pre><code>seq = 'ATTACGA'
  og_list = ['ATGGGCATAGA', 'GCCTGAACTT', 'GAATTACGAAGAGT', 'AAGTCCAAT', 'GCACATTACGATAG']
  new_list = []
  if seq in og_list:
      og_list.find(seq)
      new_list.append(seq)
  print(seq)
  </code></pre>
  <p>This is clearly not cutting it. I am unsure of how to get the next three values from the common <code>seq</code> — perhaps slicing might be effective?</p>