unable to open IDLE for Python3.50rc1 on windows10 64bit AMD

[eryk sun]

On Thu, Dec 24, 2015 at 4:45 PM, Terry Reedy <tjreedy at udel.edu> wrote:
>
>> This file should not exist. Python 3 stores .pyc files in a
>> __pycache__ subdirectory. It won't even run "idlelib\__init__.pyc" if
>> "idlelib\__init__.py" exists, so your installation is incomplete and
>> damaged. I suggest that you uninstall Python 3.5 and then completely
>> remove "C:\Python\Python35" before reinstalling.
>
> 'python -m xyz', where xyz is a package name (directory on disk), runs
> xyx/__main__.py (or the xyz/__pycache__/__main__...34.py compiled version).

Running "-m idlelib" still imports idlelib, which executes
__init__.py(c).  For example, I modified __init__.py to print a
message:

    C:\>py -3 -m idlelib
    Here I am.

Specifically, runpy._run_module_as_main('idlelib', 1) calls
runpy._get_module_details, which recurs to get the details for
"idlelib.__main__". but first it executes __import__("idlelib") to
"avoid catching initialization errors". It returns the module spec and
the code object. Then _run_module_as_main calls runpy._run_code to
exec the code in the namespace of __main__.

That said, Python 3's import system should ignore a .pyc beside a .py
file, because it looks for .pyc files in the __pycache__ subdirectory.
It only executes "idlelib\__init__.pyc" if the corresponding .py file
is missing. That's why I said Nicky's installation was both incomplete
(missing "__init__.py") and damaged (somehow containing a Python 2.7
"__init__.pyc"), so I suggested a completely fresh install. Apparently
that didn't help, so I presume for some reason it's not actually
installing the _tkinter extension module and its dependencies.