title: Renaming columns of a pandas dataframe without column names
body: <p>I'm trying to name the columns of my new dataframe after the dataframe.from_dict operation.</p>
  
  <p>Simply using pandas.dataframe.from_dict function:</p>
  
  <pre><code>df = pd.DataFrame.from_dict(my_dict,orient='index')
  </code></pre>
  
  <p>yields the dataframe without column headers. </p>
  
  <pre><code>data=pd.DataFrame.from_dict(my_dict,orient='index).rename(columns = {'name','number'}) 
  </code></pre>
  
  <p>This yields nothing an error : TypeError: 'set' object is not callable.</p>
  
  <p>Does anybody have a clue?</p>