"""Decodes a URL-safe Base64 encoded string into a UTF-8 string.

This function takes a URL-safe Base64 encoded string, ensures it has the correct padding by adding '=' characters as needed, and then decodes it into a UTF-8 string.

Args:
    base64url (str): A URL-safe Base64 encoded string.

Returns:
    str: The decoded UTF-8 string.
"""
You should write code starting with:
from base64 import urlsafe_b64decode

def str_from_base64url(base64url: str) -> str:
    # TODO: Implement this function
    pass

