code: def set_value(self, var_name, value):
          
          if var_name in self.outside_name_map:
              var_name = self.outside_name_map[var_name]
              print('%s=%.5f' % (var_name, 1e9*value))
              if var_name == 'Precipitation':
                  value = 1e9*value
          species_idx = self.species_name_map[var_name]
          self.state[species_idx] = value
docs: Set the value of a given variable to a given value.
  
          Parameters
          ----------
          var_name : str
              The name of the variable in the model whose value should be set.
  
          value : float
              The value the variable should be set to