How to decode the "categories" and "trigger" parameters of an iCalendar?

Question

I want to extract information from an .ics file and I am having problems with certain parameters. When extracting "categories" the encoded information appears, and with the "trigger" parameter I can't directly extract anything. I have tried many alternatives and none have worked.

import icalendar
from icalendar import Calendar, Event, vCalAddress, vText
from datetime import datetime
from pathlib import Path
import os

datos = {"CATEGORIES": [],
         "DTSTART": [],
         "SUMMARY": [],
         "DESCRIPTION": [],
         "TRIGGER": [],
         }

e = open('C:/Users/XXX/PycharmProjects/XXX/Calendario ALEMANIA.ics', 'r', encoding='utf-8')
ecal = icalendar.Calendar.from_ical(e.read())
for component in ecal.walk():
    if component.name == "VEVENT":
        categories = component.get("categories")
        datos["CATEGORIES"].append(categories)
        dtstart = component.decoded("dtstart")
        datos["DTSTART"].append(dtstart)
        summary = component.get("summary")
        datos["SUMMARY"].append(summary)
        description = component.decoded("description")
        datos["DESCRIPTION"].append(description)
        trigger = component.get("trigger")
        datos["TRIGGER"].append(trigger)

e.close()
print(datos)

I get this result in the two mentioned categories:

{'TRIGGER': [None], 'CATEGORIES': [<icalendar.prop.vCategory object at 0x0000011240C056C0>]}

When actually (info from the .ics) should give me:

{'TRIGGER': [-PT15M], 'CATEGORIES': [Categoría Roja]}

I have tried many functions and I GET NOTHING... Some of them:

.decode('utf-8') , component.decode("categories") , .from_ical() , .ical()...

Anyone who can help me? Regards!