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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 authentications_spec(self):
 """Spec for a group of authentication options"""

        return container_spec(authentication_objs.Authentication
              , dictof(string_spec(), set_options(
                  reading = optional_spec(authentication_spec())
                , writing = optional_spec(authentication_spec())
                )
              )
            )