title: Remove first duplicate element of a list
body: <p>I need to remove the duplicate occurrence of the 1st element in the list which is duplicate (present more than once) while preserving the order of the input list. For eg: for the input of 
      in = [2, 3, 4, 5, 3, 6, 4, 1]
  output should be 
      out = [2, 3, 4, 5, 6, 4, 1]</p>
  
  <p>I have tried below and is giving correct result , I just wanted to check with the community if there is a better or more pythonic solution to this</p>
  
  <pre><code>input = [2, 3, 4, 5, 3, 6, 4, 1]
  first_dupe = None
  for elem in input:
      if input.count(elem) &gt; 1:
          first_dupe = elem
          break
  
  flg = True
  new_list = []
  for x in input:
      if x != first_dupe or flg is True:
          new_list.append(x)
          if x == first_dupe:
               flg = False
  
  print(new_list)
  </code></pre>