title: error while "from sklearn import datasets"
body: <pre><code>from sklearn import datasets
  </code></pre>
  
  <p>When running the above code, I got an error:</p>
  
  <pre><code>`Traceback` (most recent call last):
    File "perceptron_ml.py", line 2, in &lt;module&gt;
      from sklearn import datasets
    File "/home/remember/.local/lib/python3.6/site-packages/sklearn/datasets/__init__.py", line 22, in &lt;module&gt;
      from ._twenty_newsgroups import fetch_20newsgroups
    File "/home/remember/.local/lib/python3.6/site-packages/sklearn/datasets/_twenty_newsgroups.py", line 45, in &lt;module&gt;
      from ..feature_extraction.text import CountVectorizer
    File "/home/remember/.local/lib/python3.6/site-packages/sklearn/feature_extraction/__init__.py", line 8, in &lt;module&gt;
      from ._hashing import FeatureHasher
  ImportError: cannot import name 'FeatureHasher'
  </code></pre>
  
  <p>Ubuntu: 18.04, Python: 3.6.9, Numpy: 1.17.4, scikit-learn: 0.22</p>