I installed **Python 3.5.1** on my Mac, **alongside Python 2.7.10**. When I run `python --version`, it returns `Python 2.7.10`, and when I run `python3 --version`, it returns `Python 3.5.1`, which should confirm that Python 3 correctly installed. However, whenever I try to run a command or file with **python3** in **Terminal**, it gives me this error:

> 
> Fatal Python error: Py\_Initialize: unable to load the file system
>  codec File
>  "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings/**init**.py",
>  line 123
>  raise CodecRegistryError,\
>  ^ SyntaxError: invalid syntax
> 
> 
> Current thread 0x00007fff72bb4000 (most recent call first): Abort
>  trap: 6 Farshids-MacBook-Pro-2:mysite Sasha$ python3 Fatal Python
>  error: Py\_Initialize: unable to load the file system codec File
>  "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings/**init**.py",
>  line 123
>  raise CodecRegistryError,\
>  ^ SyntaxError: invalid syntax
> 
> 
> Current thread 0x00007fff72bb4000 (most recent call first): Abort
>  trap: 6
> 
> 
> 

and also pops up with a message saying `"Python quit unexpectedly."` As you can see in the error, it mentions 2.7, which means that it was probably trying to run the code using 2.7.

How do I fix this? By the way, I installed Python 3 to follow a Django tutorial that does not work without Python 3, and I'm so knowledgeable about Python to be able to adjust.