I want to call same function from another class-object. I try this but doesn't work.Any help please.

class ClassA(models.Model):
    _name = 'class.a'
        def action_button(self):
              ......
        }

class ClassB(models.Model):
    _name = 'class.b'
    def call_func_b(self):
        self.env["class.b"].action_button()

 <button name="call_func_b" type="object" string="Create Action b"/>


class ClassC(models.Model):
    _name = 'class.c'
    def call_func_c(self):
        self.env["class.c"].action_button()

 <button name="call_func_c" type="object" string="Create Action c"/>