title: TypeError: Expected unicode, got pandas._libs.properties.CachedProperty
body: <p>I,m trying to add empty column in my dataset on colab but it give me this error.  does anybody know possible solution for this?</p>
  <p>My code.</p>
  <pre><code>dataframe[&quot;Comp&quot;] = ''
  dataframe[&quot;Negative&quot;] = ''
  dataframe[&quot;Neutral&quot;] = ''
  dataframe[&quot;Positive&quot;] = ''
  dataframe
  </code></pre>
  <p>Error message</p>
  <p>TypeError: Expected unicode, got pandas._libs.properties.CachedProperty</p>