title: Search for duplicates of items in list within list
body: <p>Working on a basic project to simulate the life cycle of an organism using matplotlib. The organism's position is defined by list [x,y], and its position is randomly generated. Organism being the class</p>
  
  <pre><code>    for i in range(numorganisms):
          posX = random.randint(0,XMAX)
          posY = random.randint(0,YMAX)
          creatures.append(organism([posX,posY]))
  </code></pre>
  
  <p>There may be about 100 of these in the plot, meaning collisions will occur. I want to be able to search the list of creatures for instances where posX and posY are both equal, and then create a new list of those positions.</p>