title: Finding the unique subset of elements in list of sets
body: <p>I am trying to find the unique determining subset(s) of a set in a list of sets, i.e. a subset E of set A such that A is the only set containing E (I'm not sure mathematically how to call it).
  For example, for the following list of sets:</p>
  
  <pre><code>set A: {2,3,5}
  set B: {2,3}
  set C: {2,3,7}
  set D: {3,7}
  set E: {2,11,13}
  set F: {2}
  </code></pre>
  
  <p>The unique subset are:</p>
  
  <pre><code>set A: {5}
  set B: {}
  set C: {2,7}
  set D: {}
  set E: {{11},{13},{11,13}}
  set F: {}
  </code></pre>
  
  <p>And the result shows relationships like given the set contains 2 and 7 it must be set C, or we can't determine a unique set if we only has element 3. Note that the elements do not necessarily need to be numbers, they can be any objects.</p>