Cannot run pip/pip3 command OS X
<p>When trying to install scikit-learn I encountered an error:</p>

<pre><code>$ pip3 install scikit-learn
-bash: pip3: command not found here

$ pip install scikit-learn
-bash: pip3.4: command not found
</code></pre>

<p>How do I resolve this? I've already tried uninstalling pip and reinstalling it via python3, but nothing seems to work.</p>

<p>Pip3, however, does still seem to be installed on my machine:</p>

<pre><code>$ locate pip3
/opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/python/py-pip/files/pip33
/opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/python/py-pip/files/pip34
/usr/local/Cellar/python3/3.4.3/bin/pip3
/usr/local/Cellar/python3/3.4.3/bin/pip3.4
/usr/local/Cellar/python3/3.5.0/bin/pip3
/usr/local/Cellar/python3/3.5.0/bin/pip3.5
/usr/local/Cellar/python3/3.5.1/bin/pip3
/usr/local/Cellar/python3/3.5.1/bin/pip3.5
/usr/local/bin/pip3
/usr/local/bin/pip3.5
</code></pre>