Log Message:
py-icalendar: update to 6.1.0.

Minor changes:
    Add end, start, duration, DTSTART, DUE, and DURATION attributes to Todo \ 
components. See Issue 662.
    Add DTSTART, TZOFFSETTO and TZOFFSETFROM properties to TimezoneStandard and \ 
TimezoneDaylight. See Issue 662.
    Format test code with Ruff. See Issue 672.
    Document the Debian package. See Issue 701.
    Document vDatetime.from_ical
    Allow passing a datetime.date to TZP.localize_utc and TZP.localize methods.
    Document component classes with description from RFC 5545.
    Merge “File Structure” and “Overview” sections in the docs. See \ 
Issue 626.
    Update code blocks in usage.rst with the correct lexer.
    Tidy up the docstring for icalendar.prop.vPeriod.
    Improve typing and fix typing issues

New features:
    Add VALARM properties for RFC 9074. See Issue 657
    Test compatibility with Python 3.13
    Add Timezone.from_tzinfo() and Timezone.from_tzid() to create a Timezone \ 
component from a datetime.tzinfo timezone. See Issue 722.
    Add icalendar.prop.tzid_from_tzinfo.
    Add icalendar.alarms module to calculate alarm times. See Issue 716.
    Add Event.alarms and Todo.alarms to access alarm calculation.
    Add Component.DTSTAMP and Component.LAST_MODIFIED properties for datetime in UTC.
    Add Component.is_thunderbird() to check if the component uses custom \ 
properties by Thunderbird.
    Add X_MOZ_SNOOZE_TIME and X_MOZ_LASTACK properties to Event and Todo.
    Add Alarm.ACKNOWLEDGED, Alarm.TRIGGER, Alarm.REPEAT, and Alarm.DURATION \ 
properties as well as Alarm.triggers to calculate alarm triggers.
    Add __doc__ string documentation for vDate, vBoolean, vCalAddress, \ 
vDuration, vFloat, vGeo, vInt, vPeriod, vTime, vUTCOffset and vUri. See Issue \ 
742.
    Add DTSTART, TZOFFSETTO, and TZOFFSETFROM to TimezoneStandard and \ 
TimezoneDaylight
    Use example methods of components without arguments.
    Add events, timezones, and todos property to Calendar for nicer access.
    To calculate which timezones are in use and add them to the Calendar when \ 
needed these methods are added: get_used_tzids, get_missing_tzids, and \ 
add_missing_timezones.
    Identify the TZID of more timezones from dateutil.
    Identify totally unknown timezones using a UTC offset lookup tree generated \ 
in icalendar.timezone.equivalent_timezone_ids and stored in \ 
icalendar.timezone.equivalent_timezone_ids.
    Add icalendar.timezone.tzid to identify a timezone’s TZID.

Bug fixes:
    Add icalendar.timezone to the documentation.