docs: def run(self):
          """Run check for duplicates"""
  
          # Create dictonary of signatures
          database_signatures = {}
          for entry in self._model.reactions:
              signature = reaction_signature(
                  entry.equation, direction=self._args.compare_direction,
                  stoichiometry=self._args.compare_stoichiometry)
              database_signatures.setdefault(signature, set()).add(
                  (entry.id, entry.equation, entry.filemark))
  
          for reaction_set in itervalues(database_signatures):
              if len(reaction_set) > 1:
                  print('Found {} duplicate reactions:'.format(
                      len(reaction_set)))
                  for reaction, equation, filemark in reaction_set:
                      result = ' - {}: {}'.format(reaction, equation)
                      if filemark is not None:
                          result += ' (found in {})'.format(filemark)
                      print(result)