title: Python How to change default version back from python 3.5 to python 2.7
body: <p>Recently, I just installed anaconda3 for python3, it works well. But then I found out that my python default version has been modified to python3.5 as well. When I type "python" in terminal, it appears like this</p>
  
  <pre><code>Python 3.5.1 |Anaconda 2.4.1 (x86_64)| (default, Dec  7 2015, 11:24:55)
  </code></pre>
  
  <p>So I go and check my bash_profile, and found why it has been changed to python3.5:</p>
  
  <pre><code># Setting PATH for Python 3.5
  # The orginal version is saved in .bash_profile.pysave
  PATH="/Library/Frameworks/Python.framework/Versions/3.5/bin:${PATH}"
  export PATH
  
  # added by Anaconda3 2.4.1 installer
  export PATH="//anaconda/bin:$PATH"
  
  # added by Anaconda3 2.4.1 installer
  export PATH="/Users/chengluli/anaconda/bin:$PATH"
  
  # added by Anaconda3 2.4.1 installer
  export PATH="/Users/chengluli/anaconda/bin:$PATH"
  export PATH="$HOME/.rbenv/bin:$PATH"
  eval "$(rbenv init -)"
  export PATH="$HOME/.rbenv/bin:$PATH"
  eval "$(rbenv init -)"
  eval "$(rbenv init -)"
  </code></pre>
  
  <p>After I commented all the texts related to python3.5 and anaconda3. The default changes to python2.7.</p>
  
  <p><strong>However, the problem I have now is anaconda3 is not working. When I type ipython notebook, error occurs.</strong></p>
  
  <p>So I wonder how can I change default python version while having anaconda3 work properly? Or anaconda3 can only work when the default is python3.5. So I need to use anaconda2 instead? Thanks in advance!</p>