title: module 'sklearn.metrics' has no attribute 'davies_bouldin_score'
body: <p>I am trying to evaluate a clustering kmeans model using sklearn.metrics.davies_bouldin_score. I am using google colab with runtime Python 3 and GPU accelerator.</p>
  
  <p>I got this error:
  module 'sklearn.metrics' has no attribute 'davies_bouldin_score'.
  <img src="https://i.stack.imgur.com/ETmJ2.png" alt="image of the error"></p>
  
  <p>I have tried to import metrics package in different ways as it was suggested by some people as <code>from sklearn import metrics</code> and <code>import sklearn.metrics</code>. It made no difference. </p>
  
  <p>I have also updated sklearn package <code>!pip install --upgrade sklearn</code> and it did not solve the problem. </p>
  
  <p>Is it google-colaboratory? How can I solve it?</p>