title: brew install python for scrapy - symlink & permission issues
body: <p>I'm following the Scrapy installation guide to install a fresh copy of python (2.7.11) despite I already have 2.6, 2.7.10 and 3.4.0. The installation was going fine until the final step with these errors</p>
  
  <pre><code>==&gt; Pouring python-2.7.11.el_capitan.bottle.2.tar.gz
  Error: The `brew link` step did not complete successfully
  The formula built, but is not symlinked into /usr/local
  Could not symlink bin/2to3
  Target /usr/local/bin/2to3
  already exists. You may want to remove it:
    rm '/usr/local/bin/2to3'
  
  To force the link and overwrite all conflicting files:
    brew link --overwrite python
  
  To list all files that would be deleted:
    brew link --overwrite --dry-run python
  
  Possible conflicting files are:
  /usr/local/bin/2to3 -&gt; /Library/Frameworks/Python.framework/Versions/3.4/bin/2to3
  Error: Permission denied - /usr/local/Frameworks
  </code></pre>
  
  <p>Moreover </p>
  
  <pre><code>ls -l /usr/local/Frameworks
  ls: /usr/local/Frameworks: No such file or directory
  </code></pre>
  
  <p>and </p>
  
  <pre><code>ls -l /usr/local/bin/2to3
  lrwxr-xr-x  1 root  wheel  66  7 Apr  2014 /usr/local/bin/2to3 -&gt; ../../../Library/Frameworks/Python.framework/Versions/3.4/bin/2to3
  </code></pre>
  
  <p>My Questions:</p>
  
  <p>1) should I have done <code>sudo brew install python</code> instead of <code>brew install python</code>? Hopefully I don't need to uninstall 2.7.11 &amp; start over.</p>
  
  <p>2) If I do the two steps they suggest <code>rm '/usr/local/bin/2to3'</code> and <code>brew link --overwrite python</code>, would I still be able to run python 3.4.0 for non-Scrapy purposes? Presumably I should do these with <code>sudo</code>?</p>
  
  <p>3) If I did #2, would the permission problem on <code>/usr/local/Frameworks</code> resolve itself or do I need to do something else?</p>
  
  <p>Follow up:</p>
  
  <p>The suggestion to set up virtualenv is probably a good one. But I'd imagine I probably need to get the install completed first.</p>
  
  <p>I have now removed 2to3. I also tried to run <code>brew link --overwrite python</code> with sudo but it came back with this cowardly refusing to sudo brew link msg so I just went ahead and did it without sudo.</p>
  
  <p>But brew link still failed on permissions</p>
  
  <pre><code>brew link --overwrite python
  Linking /usr/local/Cellar/python/2.7.11... Error: Permission denied - /usr/local/Frameworks
  </code></pre>
  
  <p>However</p>
  
  <pre><code>ls -l /usr/local/Frameworks
  ls: /usr/local/Frameworks: No such file or directory
  </code></pre>
  
  <p>Moreover, a lot of python related links in /usr/local/bin to the existing 3.4.0 (those links owned by root) and the new 2.7.11 (owned by me). </p>
  
  <p>So what do I do now? Thanks a lot.</p>