pytz shim tzinfo exceptions on serializing events when creating

[RonnyPfannschmidt]

i have a freshly configured khal with no calendar elements

when i run

$ khal new "07:00" "07:15" --repeat daily aufstehen          /home/ronny/Projects/RonnyPfannschmidt/khal/khal/icalendar.py:104: PytzUsageWarning: The localize method is no longer necessary, as this time zone supports the fold attribute (PEP 495). For more details on migrating to a PEP 495-compliant implementation, see https://pytz-deprecation-shim.readthedocs.io/en/latest/migration.html
  dtstart = timezone.localize(dtstart)
/home/ronny/Projects/RonnyPfannschmidt/khal/khal/icalendar.py:105: PytzUsageWarning: The localize method is no longer necessary, as this time zone supports the fold attribute (PEP 495). For more details on migrating to a PEP 495-compliant implementation, see https://pytz-deprecation-shim.readthedocs.io/en/latest/migration.html
  dtend = timezone.localize(dtend)
/home/ronny/Projects/RonnyPfannschmidt/khal/venv/lib/python3.9/site-packages/icalendar/parser.py:54: PytzUsageWarning: The zone attribute is specific to pytz's interface; please migrate to a new time zone provider. For more details on how to do so, see https://pytz-deprecation-shim.readthedocs.io/en/latest/migration.html
  if hasattr(dt.tzinfo, 'zone'):
/home/ronny/Projects/RonnyPfannschmidt/khal/venv/lib/python3.9/site-packages/icalendar/parser.py:55: PytzUsageWarning: The zone attribute is specific to pytz's interface; please migrate to a new time zone provider. For more details on how to do so, see https://pytz-deprecation-shim.readthedocs.io/en/latest/migration.html
  tzid = dt.tzinfo.zone  # pytz implementation
Traceback (most recent call last):
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/venv/bin/khal", line 33, in <module>
    sys.exit(load_entry_point('khal', 'console_scripts', 'khal')())
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/venv/lib/python3.9/site-packages/click/core.py", line 1128, in __call__
    return self.main(*args, **kwargs)
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/venv/lib/python3.9/site-packages/click/core.py", line 1053, in main
    rv = self.invoke(ctx)
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/venv/lib/python3.9/site-packages/click/core.py", line 1659, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/venv/lib/python3.9/site-packages/click/core.py", line 1395, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/venv/lib/python3.9/site-packages/click/core.py", line 754, in invoke
    return __callback(*args, **kwargs)
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/venv/lib/python3.9/site-packages/click/decorators.py", line 26, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/khal/cli.py", line 388, in new
    new_func(
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/khal/controllers.py", line 355, in new_from_string
    new_from_args(
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/khal/controllers.py", line 381, in new_from_args
    collection.new(event)
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/khal/khalendar/khalendar.py", line 208, in new
    event.href, event.etag = self._storages[calendar].upload(event)
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/khal/khalendar/vdir.py", line 212, in upload
    if not isinstance(item.raw, str):
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/khal/khalendar/event.py", line 382, in raw
    timezone = create_timezone(tzinfo, self.start)
  File "/home/ronny/Projects/RonnyPfannschmidt/khal/khal/khalendar/event.py", line 858, in create_timezone
    for one, two in iter(tz._tzinfos.items())
AttributeError: '_PytzShimTimezone' object has no attribute '_tzinfos'

its possibly related to the api changes in pytz and i'll slowly investigate it

[RonnyPfannschmidt]

closing as
Duplicate of #1092

eventually solved in #1093