我需要根据用户在odoo中选择的月份来获取月份的开始日期和结束日期

class MonthSelection(models.Model):
    _name = 'month.selection'
    
    month = fields.Selection([
        ('1', 'January'),
        ('2', 'February'),
        ('3', 'March'),
        ('4', 'April'),
        ('5', 'May'),
        ('6', 'June'),
        ('7', 'July'),
        ('8', 'August'),
        ('9', 'September'),
        ('10', 'October'),
        ('11', 'November'),
        ('12', 'December')
    ], string='Month', required=True)

class MonthSelection(models.Model):
    _name = 'month.selection'
    
    month = fields.Selection([
        ('1', 'January'),
        ('2', 'February'),
        ('3', 'March'),
        ('4', 'April'),
        ('5', 'May'),
        ('6', 'June'),
        ('7', 'July'),
        ('8', 'August'),
        ('9', 'September'),
        ('10', 'October'),
        ('11', 'November'),
        ('12', 'December')
    ], string='Month', required=True)
    
    start_date = fields.Date(string='Start Date', compute='_compute_dates')
    end_date = fields.Date(string='End Date', compute='_compute_dates')
    
    @api.depends('month')
    def _compute_dates(self):
        for record in self:
            year = datetime.now().year
            month = int(record.month)
            start_date = datetime(year, month, 1).date()
            end_date = (datetime(year, month, calendar.monthrange(year, month)[1])
                        .date())
            record.start_date = start_date
            record.end_date = end_date

<record id="view_month_selection_form" model="ir.ui.view">
    <field name="name">month.selection.form</field>
    <field name="model">month.selection</field>
    <field name="arch" type="xml">
        <form string="Month Selection">
            <sheet>
                <group>
                    <field name="month"/>
                    <field name="start_date"/>
                    <field name="end_date"/>
                </group>
            </sheet>
        </form>
    </field>
</record>

<record id="action_month_selection" model="ir.actions.act_window">
    <field name="name">Month Selection</field>
    <field name="res_model">month.selection</field>
    <field name="view_mode">form</field>
    <field name="view_id" ref="view_month_selection_form"/>
</record>

<menuitem id="menu_month_selection" name="Month Selection" parent="base.menu_sales"
          action="action_month_selection"/>