title: Python: why my code does not have output?
body: <p>Trying to solve leetcode 217 using python:</p>
  <pre><code>from typing import List
  
  nums = [1,2,3,1]
  
  def containsDuplicate(self, nums: List[int]) -&gt; bool:
      hashset = set()
  
      for n in nums:
          if n in hashset:
              return True
          hashset.add(n)
      return False
  </code></pre>
  <p>I supposed to get &quot;False&quot; or &quot;True&quot; from the output window, anything wrong with my code?</p>