title: Create column named "Id" based on row index
body: <p>I would like to create a new column for my dataframe named "Id" where the value  is the row index +1.
  I would like to be like the example below:</p>
  
  <pre><code>   ID  Col1  ...
  0  1   a     ...
  1  2   b     ...
  2  3   c     ...
  </code></pre>