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Python configuration of interactive shell

I'm trying to find out how to configure the "python interactive shell" on linux (i.e. the program executed when typing python in terminal). I'm looking forward to configure stuff such as coloring ps[12], tab completion (?), etc.
I'm aware of ipython/jupyter, bpython, etc. but I don't want fancy (unnecessary?) stuff but only some colored terminal :)
Is it possible to have a kind of config file?

There is an environment variable you can set, PYTHONSTARTUP:
If this is the name of a readable file, the Python commands in that file are executed before the first prompt is displayed in interactive mode. The file is executed in the same namespace where interactive commands are executed so that objects defined or imported in it can be used without qualification in the interactive session. You can also change the prompts sys.ps1 and sys.ps2 and the hook sys.__interactivehook__ in this file.
To set the environment variable, go to your terminal and type:
$ export PYTHONSTARTUP=/path/to/my/python/file.py
($ is the prompt, not something you should type.)
Since that won't last beyond the current session, you probably want to put it in your .bashrc file.
In your /path/to/my/file.py you can do whatever Python stuff you want. For example, you might want to have the primary and secondary prompts to be green:
import sys
color = "\x1b[32m{}\x1b[m"
sys.ps1 = color.format(sys.ps1)
sys.ps2 = color.format(sys.ps2)
# We don't want variables to be around in our interactive sessions.
del color
del sys
You can do whatever you want in there. In mine, I set a history file that is written to atexit. That way, Up can go beyond the current session. I also added tab completion.

Python - Running just a single line of code, and not the rest of the Multiple lines in the Script

In - Python, inside the the IDLE, in the File Editor Window,
How do you run just a selected single line of code in the script, without having the rest of the lines of the program being runned ?

You'll have to run your line of code form command line:
With the -c (command) argument (assuming your file is named foo.py):
$ python -c 'import foo; print foo.hello()'

You can select and copy a single statement in an Idle editor (or anywhere else, for that matter), switch to the Idle Shell, and paste on the line with the >>> prompt as the bottom. (You can hit to get a clean prompt.) Then hit return just as it you had entered into the shell directly. This works for multiline statements. Being able to do this with a menu selection, hotkey, or right-click selection is on my todo list, as you are not the first to ask about this.

Basically, what we call "debugger" should be fulfilled your requirement. Many IDEs are provided "debugger tools" including IDLE. To use a debugger tool you can just simply
add break lines (any lines of code you want a program to stop while program is running),
explore your variables (when program is stop you can print out values of your variables at that time)
Click/type step to go to the next breakpoint.
This is just a roughly procedure that should be fit to your requirement.
see more: debug

How to disable creating a new python IDLE session when compiling through Notepad++?

when I'm compiling python through Notepad++ I get a new python shell ( IDLE ) everytime, but I rather just keep one fixed window, instead of a new window on another position.
So for example, when I write a script which prints "Hello World!" and compile it so that my Python Shell displays the text, and when I modify my script to "Goodbye World!" the same shell prints that text. Or that that shell gets closed, but that at the same position a new shell emerges with the new text.
Could somebody please help me I'm having a hard time figuring this out..
Many thanks in advance!

You might have noticed, that python source code does not require a compilation to get run. Python source-code is rather beeing interpreted on-the-fly, by the language "engine".
Your issue is related with the Notepad++ settings and O/S settings.
IDLE is a program, that has typically been set in O/S as an associated-application to a set of filename-extensions ( .py, etc )
If your Notepad++ Compile does not call O/S to "launch" a file, the problem ceases to exist.
Your normal step to "run" the file then would be to just re-type inside the python terminal, whenever you have saved any code-modification in Notepad++:
>>> execfile( "<<_whatever_filename_my_python_source_has_>>" ) # local DIR
>>> execfile( "C:\\someDIR\\anotherSubDIR\\runMyPYTHON.py" ) # doubled-slashes

How to stop command prompt from closing in python?

I am very new to python.. I used the code
x = input(" Hey what is your name " )
print(" Hey, " + x)
input(" press close to exit ")
Because i have looked for this problem on internet and came to know that you have to put some dummy input line at the end to stop the command prompt from getting closed but m still facing the problem.. pls Help
I am using python 3.3

On windows, it's the CMD console that closes, because the Python process exists at the end.
To prevent this, open the console first, then use the command line to run your script. Do this by right-clicking on the folder that contains the script, select Open console here and typing in python scriptname.py in the console.
The alternative is, as you've found out, to postpone the script ending by adding a input() call at the end. This allows the user of the script to choose when the script ends and the console closes.

That can be done with os module. Following is the simple code :
import os
os.system("pause")
This will generate a pause and will ask user to press any key to continue.
[edit: The above method works well for windows os. It seems to give problem with mac (as pointed by ihue, in comments). The thing is that "os" library is operating system specific and some commands might not work with one operating system like they work in another one.]

For Windows Environments:
If you don't want to go to the command prompt (or work in an environment where command prompt is restricted), I think the following solution is gooThe solution I use is to create a bat file.
Use notepad to create a text file. In the file the contents will look something like:
my_python_program.py
pause
Then save the file as "my_python_program.bat" - DO NOT FORGET TO SELECT "All Files!
When you run the bat file it will run the python program and pause at the end to allow you to read the output. Then if you press any key it will close the window.

Just Add Simple input At The End Of Your Program it Worked For Me
input()
Try it And It Will Work Correctly

Try this,
import sys
status='idlelib' in sys.modules
# Put this segment at the end of code
if status==False:
input()
This will only stop console window, not the IDLE.

How can I stop python.exe from closing immediately after I get an output? [duplicate]

This question already has answers here:
How to keep a Python script output window open?
(27 answers)
Closed 8 years ago.
Is there any way I can stop python.exe from closing immediately after it completes? It closes faster than I can read the output.
Here is the program:
width = float(input("Enter the width: "))
height = float(input("Enter the height: "))
area = width * height
print("The area is", area, "square units.")

You can't - globally, i.e. for every python program. And this is a good thing - Python is great for scripting (automating stuff), and scripts should be able to run without any user interaction at all.
However, you can always ask for input at the end of your program, effectively keeping the program alive until you press return. Use input("prompt: ") in Python 3 (or raw_input("promt: ") in Python 2). Or get used to running your programs from the command line (i.e. python mine.py), the program will exit but its output remains visible.

Just declare a variable like k or m or any other you want, now just add this piece of code at the end of your program
k=input("press close to exit")
Here I just assumed k as variable to pause the program, you can use any variable you like.

For Windows Environments:
If you don't want to go to the command prompt (or work in an environment where command prompt is restricted), I think the following solution is better than inserting code into python that asks you to press any key - because if the program crashes before it reaches that point, the window closes and you lose the crash info. The solution I use is to create a bat file.
Use notepad to create a text file. In the file the contents will look something like:
my_python_program.py
pause
Then save the file as "my_python_program.bat"
When you run the bat file it will run the python program and pause at the end to allow you to read the output. Then if you press any key it will close the window.

Auxiliary answer
Manoj Govindan's answer is correct but I saw that comment:
Run it from the terminal.
And got to thinking about why this is so not obvious to windows users and realized it's because CMD.EXE is such a poor excuse for a shell that it should start with:
Windows command interpreter copyright 1999 Microsoft
Mein Gott!! Whatever you do, don't use this!!
C:>
Which leads me to point at https://stackoverflow.com/questions/913912/bash-shell-for-windows

It looks like you are running something in Windows by double clicking on it. This will execute the program in a new window and close the window when it terminates. No wonder you cannot read the output.
A better way to do this would be to switch to the command prompt. Navigate (cd) to the directory where the program is located and then call it using python. Something like this:
C:\> cd C:\my_programs\
C:\my_programs\> python area.py
Replace my_programs with the actual location of your program and area.py with the name of your python file.

Python files are executables, which means that you can run them directly from command prompt(assuming you have windows). You should be able to just enter in the directory, and then run the program.
Also, (assuming you have python 3), you can write:
input("Press enter to close program")
and you can just press enter when you've read your results.

In windows, if Python is installed into the default directory (For me it is):
cd C:\Python27
You then proceed to type
"python.exe "[FULLPATH]\[name].py"
to run your Python script in Command Prompt