title: Cannot run python 3.5 along with python 2.7.4 in Windows 10
body: <p>I am trying to install Python 3.5.0 alongside with Python 2.7.4.</p>
  
  <pre><code>C:\Users\Animesh&gt;python
  Python 2.7.4 (default, Apr  6 2013, 19:55:15) [MSC v.1500 64 bit (AMD64)] on win32
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt;
  
  C:\Users\Animesh&gt;py
  Python 2.7.4 (default, Apr  6 2013, 19:55:15) [MSC v.1500 64 bit (AMD64)] on win32
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt;
  
  C:\Users\Animesh&gt;py -2
  Python 2.7.4 (default, Apr  6 2013, 19:55:15) [MSC v.1500 64 bit (AMD64)] on win32
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt;
  
  C:\Users\Animesh&gt;py -3
  Fatal Python error: Py_Initialize: unable to load the file system codec
    File "E:\Python27\Lib\encodings\__init__.py", line 123
      raise CodecRegistryError,\
                              ^
  SyntaxError: invalid syntax
  
  Current thread 0x00003514 (most recent call first):
  </code></pre>
  
  <p>I tried a bunch of commands as shown above but python 3.5 does not seem to work. I even tried creating a project on PyCharm using the Python 3.5 interpreter but it gives that same error.</p>
  
  <p>How should I rectify this error?</p>