old_contents: # -*- coding: utf-8 -*-
  # Part of Odoo. See LICENSE file for full copyright and licensing details.
  
  from odoo import api, fields, models
  
  
  class ProjectConfiguration(models.TransientModel):
      _name = 'project.config.settings'
      _inherit = 'res.config.settings'
  
      company_id = fields.Many2one('res.company', string='Company', required=True,
          default=lambda self: self.env.user.company_id)
      module_pad = fields.Boolean("Collaborative Pads")
      module_hr_timesheet = fields.Boolean("Timesheets")
      module_project_timesheet_synchro = fields.Boolean("Awesome Timesheet")
      module_rating_project = fields.Boolean(string="Rating on Tasks")
      module_project_forecast = fields.Boolean(string="Forecasts")
      module_hr_holidays = fields.Boolean("Leave Management")
      module_hr_timesheet_attendance = fields.Boolean("Attendances")
      module_sale_timesheet = fields.Boolean("Time Billing")
      module_hr_expense = fields.Boolean("Expenses")
      group_subtask_project = fields.Boolean("Sub-tasks", implied_group="project.group_subtask_project")
  
new_contents: # -*- coding: utf-8 -*-
  # Part of Odoo. See LICENSE file for full copyright and licensing details.
  
  from odoo import api, fields, models
  
  
  class ProjectConfiguration(models.TransientModel):
      _name = 'project.config.settings'
      _inherit = 'res.config.settings'
  
      company_id = fields.Many2one('res.company', string='Company', required=True,
          default=lambda self: self.env.user.company_id)
      module_pad = fields.Boolean("Collaborative Pads")
      module_hr_timesheet = fields.Boolean("Timesheets")
      module_project_timesheet_synchro = fields.Boolean("Awesome Timesheet")
      module_rating_project = fields.Boolean(string="Rating on Tasks")
      module_project_forecast = fields.Boolean(string="Forecasts")
      module_hr_holidays = fields.Boolean("Leave Management")
      module_hr_timesheet_attendance = fields.Boolean("Attendances")
      module_sale_timesheet = fields.Boolean("Time Billing")
      module_hr_expense = fields.Boolean("Expenses")
      group_subtask_project = fields.Boolean("Sub-tasks", implied_group="project.group_subtask_project")
  
      @api.onchange('module_sale_timesheet')
      def _onchange_module_sale_timesheet(self):
          if self.module_sale_timesheet:
              self.module_hr_timesheet = True
  
subject: Enable `Timesheets` option if `Time Billing` is enabled