title: Appending New Row to Existing Dataframe using Pandas
body: <p>I'm trying to using pandas to append a blank row based on the values in the first column. When the first six characters in the first column don't match, I want an empty row between them (effectively creating groups). Here is an example of what the output could look like:</p>
  <p>002446</p>
  <p>002447-01<br />
  002447-02</p>
  <p>002448</p>
  <p>This is what I was able to put together thus far.</p>
  <pre class="lang-py prettyprint-override"><code>readie=pd.read_csv('title.csv')
  i=0
  for row in readie:
      readie.append(row)
      i+=1
      if readie['column title'][i][0:5]!=readie['column title'][i+1][0:5]:
          readie.append([])
  </code></pre>
  <p>When running this code, I get the following error message:</p>
  <pre class="lang-py prettyprint-override"><code>TypeError: cannot concatenate object of type '&lt;class 'str'&gt;'; only Series and DataFrame objs are valid
  </code></pre>
  <p>I believe there are other ways to do this, but I would like to use pandas if at all possible.</p>