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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _compute_page_url(self):
 """Compute the page url."""

        for page in self:
            base_url = self.env['ir.config_parameter'].sudo().get_param(
                'web.base.url',
                default='http://localhost:8069'
            )

            page.page_url = (
                '{}/web#db={}&id={}&view_type=form&'
                'model=document.page.history').format(
                    base_url,
                    self.env.cr.dbname,
                    page.id
                )