Python help(csv) error

Using python 3.8 in a taskwindow I get an error when trying to get help on the external module csv. (it works ok on the mac).

The csv module itself works as expected. dir(csv) also works.
It would be useful to know if the problem is with my installation or is more general.
It is very easy to reproduce.
In a taskwindow key:-

*python3
>>> import csv
>>> help(csv)

SyntaxError: invalid or missing encoding declaration for ‘SCSI::SSD.$.Apps.Development.!Python3.python38.lib.lib-dynload._csv’

Help in the form dir( object ) or help( object.method ) is only useful on Python3.10. That’s been my experience with Python on RISC OS.

Help in the form dir( object ) or help( object.method ) is only useful on Python3.10

I have tested help(module) for all the modules listed in 3.8. That is the standard modules and extra ones that Chris J supplied, ie riscos, pip, swi etc and youtube_dl, and pygame.
They all produce sensible output, so there must be something different about the csv module.

On RISC OS

>>> help(list.extend)
>>> extend(...)

extend(self, iterable, /)
    Extend list by appending elements from the iterable.

John, are we seeing the same thing?

Andrew, yes I see the same as you for help(list.extend) using 3.8
There does seem to be a whole level of help missing.
help(list) produces high level output only including

>>> help(list)
Help on class list in module builtins:
class list(object)
| Methods defined here:
………
|
| extend(…)
|
| index(…)
………

I am not using 3.10 yet – still recovering from the shock of 2.7 to 3.8 transition.

If you do the following in 3.10 what do you get?

import csv
help(csv)

On both versions, I get the same result except for any detailed messages in Python3.8.

If I enter help(csv.writer), the results are what you’d expect.

If I type help(csv), I encounter error messages.

A bit more on this.

Python 3.8.8+ (riscos-1, Feb 22 2021, 21:48:54) 
[GCC 4.7.4] on riscos
Type "help", "copyright", "credits" or "license" for more information.
>>> import csv
>>> dir(csv)
['Dialect', 'DictReader', 'DictWriter', 'Error', 'QUOTE_ALL', 'QUOTE_MINIMAL', 'QUOTE_NONE', 'QUOTE_NONNUMERIC', 'Sniffer', 'StringIO', '_Dialect', '__all__', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__', '__version__', 'excel', 'excel_tab', 'field_size_limit', 'get_dialect', 'list_dialects', 're', 'reader', 'register_dialect', 'unix_dialect', 'unregister_dialect', 'writer']
>>> help(csv.reader)
Help on built-in function reader in module _csv:

reader(...)

>>> help(csv.DictWriter)
Help on class DictWriter in module csv:

class DictWriter(builtins.object)
 |  DictWriter(f, fieldnames, restval='', extrasaction='raise', dialect='excel', *args, **kwds)
 |  
 |  Methods defined here:
 |  
 |  __init__(self, f, fieldnames, restval='', extrasaction='raise', dialect='excel', *args, **kwds)
 |  
 |  writeheader(self)
 |  
 |  writerow(self, rowdict)
 |  
 |  writerows(self, rowdicts)
 |  
 |  ----------------------------------------------------------------------
 |  Data descriptors defined here:
 |  
 |  __dict__
 |  
 |  __weakref__ 

Also, I haven’t gone into any depth, as I’m learning Python, but the module appears to work. Tested with code from here

Bug in Python3.8 Help system

This much is true:-

import(csv)
help(csv)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xec ...

>>> import csv
>>> help(csv)
Help on module csv:
NAME
    csv
CLASSES
    builtins.Exception(builtins.BaseException)
        _csv.Error
    builtins.object
        Dialect
            excel
                excel_tab
            unix_dialect
        DictReader
        DictWriter
        Sniffer    
    class Dialect(builtins.object)
     |  Describe a CSV dialect.
     .................

This much is also true
the above ‘fix’ has not upset the help sub-system.
help(module) run for all python modules.
unit-tests – strongED ListofFound:

pr15_helptest.1 : 36 hits on 36 lines
  Help on built-in module _abc:
  Help on built-in module _ast:
  Help on built-in module _codecs:
  Help on built-in module _collections:
  Help on built-in module _functools:
  Help on built-in module _imp:
  Help on module io:
  Help on built-in module _locale:
  Help on built-in module _operator:
  Help on built-in module _signal:
  Help on built-in module _sre:
  Help on built-in module _stat:
  Help on built-in module _string:
  Help on built-in module _symtable:
  Help on built-in module _thread:
  Help on built-in module _tracemalloc:
  Help on built-in module _warnings:
  Help on built-in module _weakref:
  Help on built-in module atexit:
  Help on built-in module builtins:
  Help on module easy_install:
  Help on built-in module errno:
  Help on built-in module faulthandler:
  Help on built-in module gc:
  Help on package html2text:
  Help on built-in module itertools:
  Help on built-in module marshal:
  Help on package pip:
  Help on built-in module pwd:
  Help on built-in module riscos:
  Help on package riscos_toolbox:
  Help on built-in module swi:
  Help on built-in module sys:
  Help on built-in module time:
  Help on built-in module xxsubtype:
  Help on package youtube_dl: