email validation in odoo

ODOO

we must make validation for the email field to be sure that the email which input by the user is an invalid email , and we can do that as bellow 

E.G .

let us say that we have email field as 

email = fields.Char(string="Email")

then we can make validation by adding the function bellow 

@api.constrains('email')
    def _validate_email(self):
        for rec in self:
            if self.email and not tools.single_email_re.match(rec.email):
                raise Warning(_("Please enter a valid email address."))
        return True

* to make this function work we must import tool and exceptions as bellow 

from odoo.exceptions import ValidationError

from odoo import api , fields, exceptions, tools, models,_