You can make it in your own custom module (add-on):

1. define sequence in xml file

<odoo>

<data>

<record id="<your_sequence_id>" model="ir.sequence">

<field name="name"><your_sequence_name></field>

<field name="code"><your_sequence_code></field>

<field name="prefix"><your_sequence_prefix></field>

<field name="suffix"><your_sequence_suffix></field>

<field name="padding">3</field>

<field name="number_increment">1</field>

</record>

</data>

</odoo>

there:

sequence format := <your_sequence_prefix><next_seq_number><your_sequence_suffix>

<next_seq_number> := <previous_seq_number> + <number_increment> ( 1 in this case)

<previous_seq_number> := { 0 | <previous_seq_number>}

<previous_seq_number> := <next_seq_number> - <number_increment> ( 1 in this case)

<your_sequence_prefix> := prefix format according to the legend you can find in every sequence form in ODOO,

for example PRODUCT-%(range_year)s-%(month)s-%(day)s-

<your_sequence_suffix> := suffix format according to the legend you can find in every sequence form, usually I leave it empty

<your_sequence_code> := the sequence code you will use to call it from python code,

for example myproduct.name.sequence

2. overwrite create method

@api.model

def create (self, vals):

vals['default_code'] = self.env['ir.sequence'].next_by_code('myproduct.name.sequence')

result = super ( ProductTemplate, self).create(vals)

return result

there:

myproduct.name.sequence := <your_sequence_code> defined in xml file

don't forget make default_code field read only in the form to avoid manual changes

Note: after your custom module installation this sequence will appear in ODOO sequences list