code: def setiddname(cls, iddname, testing=False):
          
          if cls.iddname == None:
              cls.iddname = iddname
              cls.idd_info = None
              cls.block = None
          elif cls.iddname == iddname:
              pass
          else:
              if testing == False:
                  errortxt = "IDD file is set to: %s" % (cls.iddname,)
                  raise IDDAlreadySetError(errortxt)
docs: Set the path to the EnergyPlus IDD for the version of EnergyPlus which
          is to be used by eppy.
  
          Parameters
          ----------
          iddname : str
              Path to the IDD file.
          testing : bool
              Flag to use if running tests since we may want to ignore the
              `IDDAlreadySetError`.
  
          Raises
          ------
          IDDAlreadySetError