I want to make a module for task dependencies as used in project management. That is: start to finish, start to start, etc relations.

I have done:

from odoo import models, fields, api
class task_dependency(models.Model):
    _inherit = 'project.task'

    start_date = fields.Date(string='Start Date')
    finish_date = fields.Date(string='Finish Date')
    task_duration = fields.Integer(string='Task Duration in Days')
    finish_to_start = fields.One2many("project.task","name", string = "Finish to Start")
    start_to_finish = fields.One2many("project.task","name", string = "Start to Finish")
    start_to_start = fields.One2many("project.task","name", string = "Start to Start")
    finish_to_finish = fields.One2many("project.task","name", string = "Finish to Finish")

How can I get the finish date of all the records from a one2many relation so I can compare, for example, all the end dates and get the greater (latest) one so I can set that as the start date of the record with the one2many?
Many thanks!!