In Odoo v8 and within a javascript file, I want to set a boolean variable to show if a user has (belongs to) an specific group or not.

I know the function, as I can use it with *.done().fail()", but I am not able to use it correctly to a variable to use later.

If I do this:

var my_var = false;
my_var = Users.call('has_group', ['import_csv_restrict.group_import_csv_allow']);

I do get a result of my_var =  [object Object], but I need it to be a boolean. How to do it?

I have also tried to do:

var my_var = false;
sers.call('has_group', ['import_csv_restrict.group_import_csv_allow'])
.done(function() {my_var = true;};)
.fail(function() {my_var = false;};);


 But my_var is actually not affected.