i have the following models,production  data is uploaded to dlc.pdata via excel without workstations with zero production so i created a function to identify missing workstations and write a value of 0 but it does not write only those not present but all .

class ProductionData(models.Model):
    _name = 'dlc.pdata'
    _rec_name = 'start_date'
    _description = 'New Description'

    name = fields.Char()
    start_date = fields.Date(string="From", required=False, )
    end_date = fields.Date(string="To", required=False,)
    production_details_ids = fields.One2many(comodel_name="dlc.pdetails", inverse_name="production_data_id", string="Production Details", required=False, )

    

    @api.multi
    @api.model_create_multi
    def process_data(self, values):
        workstation = self.env['dlc.workstation']
        dlc = set(workstation.search([]))
        pdlc = self.env['dlc.pdetails']
        domain = [('production_data_id', '=', self.id)]
        pdlct = pdlc.search(domain)
        workeddlc = set(a.workstation_id.ids[0] for a in pdlct if a.workstation_id.id)
        for x in dlc + workeddlc:
            if x not in workeddlc:
                nowork2 = x.ids
                for line in nowork2:
                    values = {
                        'workstation_id': line,
                        'production_data_id': self.id,
                        'card_type': 'Office Total',
                        'cdl': 0,
                        'gdl': 0,
                        'msl': 0,
                        'pdl': 0,
                        'sdl': 0,
                        'ddl': 0,
                        'total': 0,
                    }

                    self.env['dlc.pdetails'].create(values)


class ProductionDetails(models.Model):
    _name = 'dlc.pdetails'
    _rec_name = 'workstation_id'

    workstation_id = fields.Many2one(comodel_name="dlc.workstation", string="DLC", required=False, )
    production_data_id = fields.Many2one(comodel_name="dlc.pdata", string="Production", required=False, )
    card_type = fields.Selection(string="Card Type",
                                 selection=[('Temporary', 'Temporary'), ('Office Total', 'Office Total'),
                                            ('Permanent', 'Permanent')], required=False, )
    cdl = fields.Integer(string="CDL", required=False, )
    gdl = fields.Integer(string="GDL", required=False, )
    msl = fields.Integer(string="MSL", required=False, )
    pdl = fields.Integer(string="PDL", required=False, )
    sdl = fields.Integer(string="SDL", required=False, )
    ddl = fields.Integer(string="DDL", required=False, )
    total = fields.Integer(string="TOTAL", required=False, )

class WorkStation(models.Model):
    _name = 'dlc.workstation'
    _description = 'list of work station'

    name = fields.Char()
    dlc_operator = fields.Many2many("dlc.personnel",string="DLC Personnel")
    lga = fields.Many2one('dlc.lga')
    state = fields.Many2one('dlc.states')
    dlc_supervisor = fields.Many2one('dlc.personnel')
    issues_ids = fields.One2many(comodel_name="dlc.issues", inverse_name="dlc_id", string="Issues", required=False, )
    status = fields.Selection(string="DLC Status", selection=[('active', 'Active'), ('inactive', 'Inactive'), ], required=False, default= 'active' )
    total_dlc = fields.Integer(string="Total DLCs", required=False, compute='_total_dlc')
    inactive_dlc = fields.Integer(string="Inactive DLCs", required=False, compute='_inactive_dlc')
    dlc_cug = fields.Char(string="DLC CUG Number")