title: datetime.strptime: TypeError: strptime() argument 1 must be str, not Series
body: <p>I want to strip my date but it gives following error:</p>
  
  <pre><code>df1["Date"] = datetime.datetime.strptime(df1["Date"][:10], "%Y-%m-%d")
  TypeError: strptime() argument 1 must be str, not Series
  </code></pre>
  
  <p>This is my code:</p>
  
  <pre><code>df1["Date"] = datetime.datetime.strptime(df1["Date"][:10], "%Y-%m-%d")
  </code></pre>