title: ModuleNotFoundError: No module named 'sklearn.utils._joblib'
body: <p>I'm using python 3.6 on on Anaconda Jupyter notebooks platform. My pc uses win 8.1 as OS. </p>
  
  <p>I was trying to import PCA from sklearn using the following lines:</p>
  
  <pre><code>import sklearn
  from sklearn import decomposition 
  from sklearn.decomposition import PCA 
  </code></pre>
  
  <p>the third line returns a Module error: <code>ModuleNotFoundError: No module named 'sklearn.utils._joblib'</code></p>
  
  <p>Strangely, I couldn't find any record on this error online! I'd appreciate any help. I copied the complete error message below:</p>
  
  <pre><code>---------------------------------------------------------------------------
  ModuleNotFoundError                       Traceback (most recent call last)
  &lt;ipython-input-375-2e95ea83a366&gt; in &lt;module&gt;()
        1 import sklearn
  ----&gt; 2 from sklearn import decomposition
        3 from sklearn.decomposition import PCA
        4 # Make an instance of the Model
        5 pca = PCA(.95)
  
  E:\Anaconda3\lib\site-packages\sklearn\decomposition\__init__.py in &lt;module&gt;()
        9 from .incremental_pca import IncrementalPCA
       10 from .kernel_pca import KernelPCA
  ---&gt; 11 from .sparse_pca import SparsePCA, MiniBatchSparsePCA
       12 from .truncated_svd import TruncatedSVD
       13 from .fastica_ import FastICA, fastica
  
  E:\Anaconda3\lib\site-packages\sklearn\decomposition\sparse_pca.py in &lt;module&gt;()
       11 from ..linear_model import ridge_regression
       12 from ..base import BaseEstimator, TransformerMixin
  ---&gt; 13 from .dict_learning import dict_learning, dict_learning_online
       14 
       15 
  
  E:\Anaconda3\lib\site-packages\sklearn\decomposition\dict_learning.py in &lt;module&gt;()
       15 
       16 from ..base import BaseEstimator, TransformerMixin
  ---&gt; 17 from ..utils._joblib import Parallel, delayed, effective_n_jobs
       18 from ..externals.six.moves import zip
       19 from ..utils import (check_array, check_random_state, gen_even_slices,
  
  ModuleNotFoundError: No module named 'sklearn.utils._joblib'
  </code></pre>