Python: Check if dataframe column contain string type : <p>I want check if columns in a dataframe consists of strings so I can label them with numbers for machine learning purposes. Some columns consists of numbers, I dont want to change them. Columns example can be seen below:</p>

<pre><code>TRAIN FEATURES
  Age              Level  
  32.0              Silver      
  61.0              Silver  
  66.0              Silver      
  36.0              Gold      
  20.0              Silver     
  29.0              Silver     
  46.0              Silver  
  27.0              Silver      
</code></pre>

<p>Thank you=)</p>
