docs: def frequency(self, mapping):
          """
          Returns frequency of a given :class:`caspo.core.mapping.Mapping`
  
          Parameters
          ----------
          mapping : :class:`caspo.core.mapping.Mapping`
              A logical conjuntion mapping
  
          Returns
          -------
          float
              Frequency of the given mapping over all logical networks
  
          Raises
          ------
          ValueError
              If the given mapping is not found in the mappings of the underlying hypergraph of this list
          """
          return self.__matrix[:, self.hg.mappings[mapping]].mean()