title: Find all possible sublists of a list
body: <p>Let's say I have the following list</p>
  
  <pre><code>[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18]
  </code></pre>
  
  <p>I want to find all possible sublists of a certain lenght where they don't contain one certain number and without losing the order of the numbers.</p>
  
  <p>For example all possible sublists with length 6 without the 12 are:</p>
  
  <pre><code>[1,2,3,4,5,6]
  [2,3,4,5,6,7]
  [3,4,5,6,7,8]
  [4,5,6,7,8,9]
  [5,6,7,8,9,10]
  [6,7,8,9,10,11]
  [13,14,15,16,17,18]
  </code></pre>
  
  <p>The problem is that I want to do it in a very big list and I want the most quick way.</p>
  
  <p>Update with my method:</p>
  
  <pre><code>oldlist = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18]
  newlist = []
  length = 6
  exclude = 12
  for i in oldlist:
     if length+i&gt;len(oldlist):
         break
     else:
         mylist.append(oldlist[i:(i+length)]
  for i in newlist:
      if exclude in i:
         newlist.remove(i)
  </code></pre>
  
  <p>I know it's not the best method, that's why I need a better one.</p>