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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 created(self):
 """Return creation date :rtype: datetime :raises ResourceNotFound: resource not found on the API """

        if 'id_perms' not in self:
            self.fetch()
        created = self['id_perms']['created']
        return datetime.strptime(created, '%Y-%m-%dT%H:%M:%S.%f')