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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_modified_time(self) -> Optional[datetime.datetime]: """Returns the time that ``self.absolute_path`` was last modified. May be overridden in subclasses. Should return a `~datetime.datetime` object or None. .. versionadded:: 3.1 """

        stat_result = self._stat()
        # NOTE: Historically, this used stat_result[stat.ST_MTIME],
        # which truncates the fractional portion of the timestamp. It
        # was changed from that form to stat_result.st_mtime to
        # satisfy mypy (which disallows the bracket operator), but the
        # latter form returns a float instead of an int. For
        # consistency with the past (and because we have a unit test
        # that relies on this), we truncate the float here, although
        # I'm not sure that's the right thing to do.
        modified = datetime.datetime.utcfromtimestamp(int(stat_result.st_mtime))
        return modified