title: 2-sum problem: given an unsorted list of ints, find if two elements sum to a given target. How to make my code more Pythonic?
body: <p>I'm trying to learn about PEP-8 guidelines, writing Pythonic code, and about Python's standard libraries (am a day into this journey). Suggestions to make the following piece of code (including comments) more Pythonic would be much appreciated. I know the algorithm could be improved, but this isn't a priority at the moment - but please do write if you have an elegant solution!</p>
  
  <p>I've run it through the following PEP-8 checker, so hopefully the basics are not a problem: <a href="http://pep8online.com/checkresult" rel="nofollow noreferrer">http://pep8online.com/checkresult</a></p>
  
  <pre><code>import collections
  
  
  def two_sum(input_list, target):
      # Determine if two elements in list add to target
      # dict_of_counts -  key: element from input_list, value: count of element
      dict_of_counts = collections.Counter(input_list)
      for key in dict_of_counts:
          complement_key = target - key
          if complement_key in dict_of_counts:
              # Corner case: complement_key is the same as key,
              # but the count is one (so threat of a false +ve)
              if complement_key != key:
                  return(True)
              elif dict_of_counts[complement_key] &gt; 1:
                  return(True)
      return(False)
  </code></pre>
  
  <p>P.S. My first question ever : O !</p>