title: How to get row number in dataframe in Pandas?
body: <p>How can I get the number of the row in a dataframe that contains a certain value in a certain column using Pandas? For example, I have the following dataframe:</p>
  
  <pre><code>     ClientID  LastName
  0    34        Johnson
  1    67        Smith
  2    53        Brows  
  </code></pre>
  
  <p>How can I find the number of the row that has 'Smith' in 'LastName' column?</p>