docs: def replicate(self, info_in):
          """Replicate an info."""
          # check self is not failed
          if self.failed:
              raise ValueError("{} cannot replicate as it has failed."
                               .format(self))
  
          from transformations import Replication
          info_out = type(info_in)(origin=self, contents=info_in.contents)
          Replication(info_in=info_in, info_out=info_out)