title: How do I get total row count of Pandas Dataframe when using iterator=True
body: <p>I'm dealing with large files that doesn't fit in memory, as a result of that I'm using the iterator functionality of Pandas' Dataframe and processing single chunk each time.</p>
  
  <pre><code>pd.read_csv(csv_file_name, encoding='utf-8', chunksize=chunk_size, iterator=True,
                                              engine='c', error_bad_lines=False, low_memory=False)
  </code></pre>
  
  <p>While processing I'd like to print the number of processed rows and the percentage of processed rows out of the total amount of rows.</p>
  
  <p>To get the total amount of rows in a Pandas Dataframe I'm using </p>
  
  <pre><code>len(df.index)
  </code></pre>
  
  <p>But when trying to use it when using ierator I'm getting </p>
  
  <pre><code>AttributeError: 'TextFileReader' object has no attribute 'index'
  </code></pre>
  
  <p>Any way of doing that?  (while not going over each chunk)</p>