installing packages for python 3
<p>I tend to run my code in Jupyter notebooks, and these run in python 3. I also have python 2 on my computer. I installed <code>pip3</code> so I'd be able to install packages specifically for python 3 but this doesn't seem to be working out for me:</p>

<pre><code>mba$ pip3 install multidict
Collecting multidict
  Using cached multidict-2.1.2.tar.gz
Building wheels for collected packages: multidict
  Running setup.py bdist_wheel for multidict ... done
  Stored in directory: /Users/mba/Library/Caches/pip/wheels/6e/f3/6a/c1ff64511c3dc2964ade4f9e59f4d7dfc050bd77e0fcc78ca5
Successfully built multidict
Installing collected packages: multidict
Successfully installed multidict-2.1.2
mba:~ $ python3
Python 3.5.2 |Anaconda custom (x86_64)| (default, Jul  2 2016, 17:52:12) 
[GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
&gt;&gt;&gt; import multidict
Traceback (most recent call last):
  File "&lt;stdin&gt;", line 1, in &lt;module&gt;
ImportError: No module named 'multidict'
&gt;&gt;&gt; import sys.
  File "&lt;stdin&gt;", line 1
    import sys.
              ^
SyntaxError: invalid syntax
&gt;&gt;&gt; import sys
&gt;&gt;&gt; sys.version
'3.5.2 |Anaconda custom (x86_64)| (default, Jul  2 2016, 17:52:12) \n[GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)]'
&gt;&gt;&gt; 
</code></pre>

<p>Notice that the <code>multidict</code> install with <code>pip3</code> succeeded, but when I ran <code>python3</code> and tried to <code>import multidict</code>, this failed. How can I install the proper Python 3 version of the package I want?</p>

<p>For reference, I'm on Mac OS X El Capitan. I've read the existing SO posts and tried following the advice in these:</p>

<ul>
<li><a href="https://stackoverflow.com/questions/20082935/how-to-install-pip-for-python3-on-mac-os-x">How to install pip for Python 3 on Mac OS X?</a></li>
<li><a href="https://stackoverflow.com/questions/34573159/how-do-install-pip3-on-my-mac">How do install pip3 on my mac?</a></li>
</ul>

<p>These have not done the trick. Thanks for any suggestions. </p>