title: Append Row to Google Spreadsheet-->TypeError: keys must be a string
body: <p>I am trying to append a row to a google spreadsheet but get an error. Usually it works but now it says:</p>
  
  <pre><code>TypeError: keys must be a string
  </code></pre>
  
  <p>Does anyone know what it means?</p>
  
  <p>Here is my code and a print of all the datatypes I try to insert. Is there a problem with numpy types or boolean for spreadsheets?</p>
  
  <pre><code>for e in range(experiments):
      #types: &lt;class 'int'&gt;,&lt;class 'str'&gt;,&lt;class 'numpy.str_'&gt;,&lt;class 'float'&gt;,&lt;class 'int'&gt;,&lt;class 'int'&gt;,&lt;class 'numpy.float64'&gt;,&lt;class 'numpy.float64'&gt;,&lt;class 'numpy.float64'&gt;,&lt;class 'int'&gt;,&lt;class 'collections.defaultdict'&gt;,&lt;class 'int'&gt;,&lt;class 'int'&gt;,&lt;class 'float'&gt;,&lt;class 'bool'&gt;
  
      insertRow=[training,gameList[e],stateList[e], eps, experiments,timesteps,min_rewardList[e],maxRewList[e],total_rewList[e],currentMaxXList[e],maxXList[e],frames_stack,mb_size,learning_rate,completed_levelList[e]]
      sheet.append_row(insertRow)
  </code></pre>