Dear Sir/Madam,

Bug:
In section 2.2.2. on page http://docs.python.org/py3k/tutorial/interpreter.html you mention "On Windows systems, there is no notion of an “executable mode” ".
This is wrong. Since Windows NT4 and onwards, there is a notion of a "path extension", which is similar to the Unix executable mode, but invoked differently.

Solution:
1. Using the GUI:
a. Right-click on "My computer"
b. go to "properties"
c. go to "environment variables" (dependent on the OS: NT 4.0, W2K, XP, Vista, W7)
d. add the string ";PY" to the end of the existing string
OR
2. Using the Command line (temporary for that command interpreter only until it is exited)
At the CLI (cmd.exe; commnd.com) ">" type:
SET PATHEXT=%PATHEXT%;.PY

Python executables can now be executed on a command line without specifically invoking the Python interpreter as the Python installer automatically associates .py files with python.exe. (Which is a prerequisite)

Example:
C:\Program Files\Python\Tools\Scripts>SET PATHEXT=%PATHEXT%;.PY
C:\Program Files\Python\Tools\Scripts>2to3.py
At least one file or directory argument required.
Use --help to show usage.

HTH,

Fabrizio Marana