title: Cannot import BertModel from transformers
body: <p>I am trying to import BertModel from transformers, but it fails. This is code I am using</p>
  
  <pre><code>from transformers import BertModel, BertForMaskedLM
  </code></pre>
  
  <p>This is the error I get</p>
  
  <pre><code>ImportError: cannot import name 'BertModel' from 'transformers'
  </code></pre>
  
  <p>Can anyone help me fix this?</p>