Odoo: Unable to use a closed cursor

Question

I am trying to call a function after a response has been returned from a http request:

class SomeAPIEndpoint(http.Controller):
    @http.route('/api', type='json')
    def controller(self, **kwargs):
        data = self.function1(request)
        with api.Environment.manage():
            env = api.Environment(request.env.cr, request.env.user.id, request.env.context)
            t = threading.Thread(target=self.function2, args=(env,))
            t.start()
        return data


    def function1(self, request):
        # should return the response 
        data = request.env['some.model'].search([])
        # work with the data here ...
        return data

    def function2(self, env):
        # should not stop the response
        # triggers a cron job that gets new data from a service
        # and stores the data in some.model
        cron = env['ir.cron'].search([('id', '=', 1)])
        cron.with_user(cron.user_id).with_context(lastcall=cron.lastcall).ir_actions_server_id.run()

I want function1 to be executed and return the response and function2 to be executed after the response.

But I get Unable to use a closed cursor.

How can I solve this?

Thank you