How to use the mip.lists.EmptyRowSol function in mip

if osi_ptr != ffi.NULL:
            self.osi = osi_ptr
            self.owns_solver = False
        else:
            self.owns_solver = True
            self.osi = cbclib.Osi_newSolver()
        self.__relaxed = False

        # name indexes, created if necessary
        self.colNames = None
        self.rowNames = None
        self._objconst = 0.0
        self.osi_cutsp = ffi.NULL
        self.__x = EmptyVarSol(model)
        self.__rc = EmptyVarSol(model)
        self.__pi = EmptyRowSol(model)
        self.__obj_val = None

        if cbclib.Osi_isProvenOptimal(self.osi):
            self.__x = cbclib.Osi_getColSolution(self.osi)
            self.__rc = cbclib.Osi_getReducedCost(self.osi)
            self.__pi = cbclib.Osi_getRowPrice(self.osi)
            self.__obj_val = cbclib.Osi_getObjValue(self.osi)

def __clear_sol(self):
        model = self.model
        self.__x = EmptyVarSol(model)
        self.__rc = EmptyVarSol(model)
        self.__pi = EmptyRowSol(model)
        self.__obj_val = None

def __clear_sol(self: "SolverCbc"):
        self.__x = EmptyVarSol(self.model)
        self.__rc = EmptyVarSol(self.model)
        self.__pi = EmptyRowSol(self.model)
        self.__slack = EmptyRowSol(self.model)
        self.__obj_val = None
        self.__obj_bound = None
        self.__num_solutions = 0

def __clear_sol(self: "SolverCbc"):
        self.__x = EmptyVarSol(self.model)
        self.__rc = EmptyVarSol(self.model)
        self.__pi = EmptyRowSol(self.model)
        self.__slack = EmptyRowSol(self.model)
        self.__obj_val = None
        self.__obj_bound = None
        self.__num_solutions = 0

self.__verbose = 1
        # pre-allocate temporary space to query names
        self.__name_space = ffi.new("char[{}]".format(MAX_NAME_SIZE))
        # in cut generation
        self.__name_spacec = ffi.new("char[{}]".format(MAX_NAME_SIZE))
        self.__log = (
            []
        )  # type: List[Tuple[numbers.Real, Tuple[numbers.Real, numbers.Real]]]
        self.set_problem_name(name)
        self.__pumpp = DEF_PUMPP

        # where solution will be stored
        self.__x = EmptyVarSol(model)
        self.__rc = EmptyVarSol(model)
        self.__pi = EmptyRowSol(model)
        self.__slack = EmptyRowSol(model)
        self.__obj_val = None
        self.__obj_bound = None
        self.__num_solutions = 0

def __clear_sol(self: "SolverOsi"):
        self.__x = EmptyVarSol(self.model)
        self.__rc = EmptyVarSol(self.model)
        self.__pi = EmptyRowSol(self.model)
        self.__obj_val = None

# fine grained control of what is changed
        # for selective call on model.update
        self.__n_cols_buffer = 0
        self.__n_int_buffer = 0
        self.__n_rows_buffer = 0
        self.__n_modified_cols = 0
        self.__n_modified_rows = 0
        self.__updated = True
        self.__name_space = ffi.new("char[{}]".format(MAX_NAME_SIZE))
        self.__log = []

        # where solution will be stored
        self.__x = EmptyVarSol(model)
        self.__rc = EmptyVarSol(model)
        self.__pi = EmptyRowSol(model)
        self.__obj_val = None