Python: No module named ... How to use pip
<p>I'm a new to Python, and I have a trouble in import library.</p>

<p>I wrote a code</p>

<pre><code>from sklearn.linear_model import LogisticRegression
</code></pre>

<p>then I got an error</p>

<pre><code>ImportError                               Traceback (most recent call last)
&lt;ipython-input-19-c84b03903d9e&gt; in &lt;module&gt;()
----&gt; 1 from sklearn.linear_model import LogisticRegression

/usr/lib/python2.7/dist-packages/sklearn/linear_model/__init__.py in &lt;module&gt;()
     10 # complete documentation.
     11 
---&gt; 12 from .base import LinearRegression
     13 
     14 from .bayes import BayesianRidge, ARDRegression

/usr/lib/python2.7/dist-packages/sklearn/linear_model/base.py in &lt;module&gt;()
     22 
     23 from ..externals import six
---&gt; 24 from ..externals.joblib import Parallel, delayed
     25 from ..base import BaseEstimator, ClassifierMixin, RegressorMixin
     26 from ..utils import as_float_array, atleast2d_or_csr, safe_asarray

/usr/lib/python2.7/dist-packages/sklearn/externals/joblib/__init__.py in &lt;module&gt;()
      1 # yoh: use system-wide joblib
      2 
----&gt; 3 from joblib import *

ImportError: No module named joblib
</code></pre>

<p>in IPython.
I'm using ubuntu and I installed scikit_learn-0.18 by using "sudo apt-get install python-sklearn" command but encountered above error.
I also tried to use "sudo easy_install joblib" but the error was not erased.</p>

<p>What is wrong? Would you help me? Thank you.</p>