title: python : can reduce be translated into list comprehensions like map, lambda and filter?
body: <p>When programming in python, I now avoid <code>map</code>, <code>lambda</code> and <code>filter</code> by using list comprehensions because it is easier to read and faster in execution. But can <code>reduce</code> be replaced as well?</p>
  
  <p>E.g. an object has an operator <code>union()</code> that works on another object, <code>a1.union(a2)</code>, and gives a 3rd object of same type.</p>
  
  <p>I have a list of objects:</p>
  
  <pre><code>L = [a1, a2, a3, ...]
  </code></pre>
  
  <p>How to have the union() of all these objects with list comprehensions, the equivalent of:</p>
  
  <pre><code>result = reduce(lambda a, b :a.union(b), L[1:], L[0])
  </code></pre>