I have  three classesProductModel,BuyProduct,SoldProduct

when a user buys a  product i need  to remove item from ProductModel and insert to SoldProduct.

class ProductModel(models.Model):

_name = "product.model"

product_name=feilds.Char("Product")

product_id = feilds.Char("Id")

_sql_constraints = [

        ('uniq_product_id', 'unique(product_id)', 'id already exists'),

    ]

    @api.model

    def create(self, vals):

        id = randrange(1000, 10000)

        vals['product_id'] = "PR" + str(id)

        return super(ProductModel, self).create(vals)

class BuyProduct(models.Model):

_name = buyproduct.model

user_Name = fields.Many2one('user.model',string="Name")

    product = fields.Many2many('product.model',string="Product")

    Date = fields.Datetime(default = fields.Datetime.now(),string="Selling Date",readonly=True)

    return_Before =fields.Datetime(default = lambda self:(datetime.datetime.now() + datetime.timedelta(days=7)),string="return_Before",readonly=True)

class SoldProduct(models.Model):

_name = soldproduct.model

product_name = fields.Char("Product")

product_id = fields.Char("Id")

Thanks in advance,

Ramanathan Lakshmanan