IPython#

Table of Contents

Tips#

Tip 1: quickref#

You can use the %quickref magic command to get a quick introduction to IPythons features.

1>>> %quickref

IPython -- An enhanced Interactive Python - Quick Reference Card
================================================================

obj?, obj??      : Get help, or more help for object (also works as
                   ?obj, ??obj).
?foo.*abc*       : List names in 'foo' containing 'abc' in them.
%magic           : Information about IPython's 'magic' % functions.
...

Tip 2: Save history to file#

You can save the history from your last session to the file in the directory you were in when you started ipython by using the %save magic command.

Listing 618 ipython shell – save to a file named session.py#
1>>> %save session ~1/
The following commands were written to file `session.py`:
import requests
response = requests.get("http://api.punkapi.com/v2/beers/random")
response.ok
response.status_code
response.reason
...

Troubleshooting#

unexpected keyword argument ‘column’#

Error

This error occurs when attempting tab completion.

  File "../venv/lib/python3.8/site-packages/IPython/core/completer.py", line 2029, in _complete
    completions = self._jedi_matches(
  File "../venv/lib/python3.8/site-packages/IPython/core/completer.py", line 1373, in _jedi_matches
    interpreter = jedi.Interpreter(
  File "../venv/lib/python3.8/site-packages/jedi/api/__init__.py", line 725, in __init__
    super().__init__(code, environment=environment,
TypeError: __init__() got an unexpected keyword argument 'column'
Solution

iPython <=7.19 is incompatible with jedi version 0.18.0. To resolve, downgrade jedi to version 0.17.2.

Modify your pyproject.toml file and add the following jedi dependency just above the ipython dependency.

Listing 619 pyproject.toml#
[tool.poetry.dev-dependencies]
...
jedi = "0.17.2" # ipython <=7.19
ipython = "^7.19.0"

Then in a terminal run:

Listing 620 terminal#
poetry update jedi

In a terminal run:

Listing 621 terminal#
python -m pip install -U jedi~=0.17.2

See also

Unhandled exception in event loop#

Error

This error occurs intermittently after hitting enter.

Unhandled exception in event loop:
  File "...\lib\asyncio\proactor_events.py", line 768, in _loop_self_reading

    f.result()  # may raise
  File "...\lib\asyncio\windows_events.py", line 808, in _poll
    value = callback(transferred, key, ov)
  File "...\lib\asyncio\windows_events.py", line 457, in finish_recv
    raise ConnectionResetError(*exc.args)

Exception [WinError 995] The I/O operation has been aborted because of either a thread exit or an application request
Solution

iPython ~7.13.0 on Windows does not work with a version 3+ of prompt-toolkit. To resolve, downgrade prompt-toolkit to version 2.x.

Modify your pyproject.toml file and add the following prompt-toolkit dependency just above the ipython dependency.

Listing 622 pyproject.toml#
[tool.poetry.dev-dependencies]
...
prompt-toolkit = "^2" # ipython ~7.10
ipython = "^7.13.0"

Then in a terminal run:

Listing 623 terminal#
poetry update prompt-toolkit

In a terminal run:

Listing 624 terminal#
python -m pip install -U prompt-toolkit~=2.0

See also