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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_content_modified_time(cls, abspath):
 """Returns the time that ``abspath`` was last modified. May be overridden in subclasses. Should return a `~datetime.datetime` object or None. """

        stat_result = os.stat(abspath)
        modified = datetime.datetime.utcfromtimestamp(
            stat_result[stat.ST_MTIME])
        return modified