Unable to set IPython prompt - ipython

Question

I'm running ipython with the following:
c:\python27\scripts\ipython
I'm trying to restore old Python prompt behaviour (">>>") for some reasons.
I've tried to search internet extensively for that purpose, to no avail.
Then I reached for IPython documentation, which turned out to be confusing and unhelpful.
According to http://ipython.readthedocs.io/en/stable/config/details.html
To set the new prompt, assign it to the prompts attribute of the IPython shell:
In [2]: ip = get_ipython()
...: ip.prompts = MyPrompt(ip)
/home/bob >>> # it works
I get the exception that get_ipython is undefined:
[TerminalIPythonApp] ERROR | Exception while loading config file C:\Users\xxx\.ipython\profile_default\ipython_config.py
Traceback (most recent call last):
File "c:\python27\lib\site-packages\traitlets\config\application.py", line 562, in _load_config_files
config = loader.load_config()
File "c:\python27\lib\site-packages\traitlets\config\loader.py", line 457, in load_config
self._read_file_as_dict()
File "c:\python27\lib\site-packages\traitlets\config\loader.py", line 489, in _read_file_as_dict
py3compat.execfile(conf_filename, namespace)
File "c:\python27\lib\site-packages\ipython_genutils\py3compat.py", line 278, in execfile
exec(compiler(scripttext, filename, 'exec'), glob, loc)
File "C:\Users\rgomulk\.ipython\profile_default\ipython_config.py", line 9, in <module>
ip = get_ipython()
NameError: name 'get_ipython' is not defined
Python 2.7.8 (default, Jun 30 2014, 16:03:49) [MSC v.1500 32 bit (Intel)]
Type "copyright", "credits" or "license" for more information.
IPython 5.1.0 -- An enhanced Interactive Python.
? -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help -> Python's own help system.
object? -> Details about 'object', use 'object??' for extra details.
(With the following complete code in my ipython_config.py:
from IPython.terminal.prompts import Prompts, Token
class MyPrompt(Prompts):
def in_prompt_tokens(self, cli=None):
return [(Token.Prompt, ' >>>')]
ip = get_ipython()
ip.prompts = MyPrompt(ip)
After next round of googling I've added the following line to the config:
from IPython import get_ipython
This time the result was different:
[TerminalIPythonApp] ERROR | Exception while loading config file C:\Users\xxx\.ipython\profile_default\ipython_config.py
Traceback (most recent call last):
File "c:\python27\lib\site-packages\traitlets\config\application.py", line 562, in _load_config_files
config = loader.load_config()
File "c:\python27\lib\site-packages\traitlets\config\loader.py", line 457, in load_config
self._read_file_as_dict()
File "c:\python27\lib\site-packages\traitlets\config\loader.py", line 489, in _read_file_as_dict
py3compat.execfile(conf_filename, namespace)
File "c:\python27\lib\site-packages\ipython_genutils\py3compat.py", line 278, in execfile
exec(compiler(scripttext, filename, 'exec'), glob, loc)
File "C:\Users\rgomulk\.ipython\profile_default\ipython_config.py", line 11, in <module>
ip.prompts = MyPrompt(ip)
AttributeError: 'NoneType' object has no attribute 'prompts'
So the question is twofold:
1. How can I actually set the prompt/restore old prompt behaviour?
2. Why doesn't the code from IPython documentation work? Is that a bug in implementation or documentation?
IPython version and other versions already given in IPython output.
Regards,
Robert

Answer 1

After extensive search (it was really tedious and others are confused as well, especially from distinguishing between startup and configuration scripts) I've found this page: Jupyter prompts
Which led to (working) solution:
from IPython.terminal.prompts import Prompts
from pygments.token import Token
class MyPrompt(Prompts):
def in_prompt_tokens(self, cli=None):
return [(Token.Prompt, '>>> ')]
c.TerminalInteractiveShell.prompts_class = MyPrompt
(Please notice the lack of what seems to be required by official documentation Official IPython docs:
The files typically start by getting the root config object:
c = get_config()
Regards,
Robert

Answer 2

Another possibility - less generic - is to use predefined Prompt class:
from IPython.terminal.prompts import ClassicPrompts
c = get_config()
c.TerminalInteractiveShell.prompts_class = ClassicPrompts