It's possible to use more than one environnement in a controller class 's function??

for example if i  want to retrieve data from sale.order and sale.order.line, can i use these codes?

class controller(.....):

http.route(.....)

def function(self):

     sales = self.env['sale.order]

     #my operations

     sales_line = self.env['sale.order.line']

     #my operations

I am using odoo8

thanks