Accessing Extension with out Superuser privilege

In PostgreSQL server we created an extension with this command CREATE
EXTENSION "uuid-ossp";

For our drupal site with user "drupal_user" we are trying to access this
but getting an error as "function uuid_generate_v4() does not exist"
When we give privilege for user "drupal_user" as Superuser we are able to
access it.

So please let us know with out giving Superuser privilege how we can give
permission for "drupal_user" to access extension or let me know what
additional role other than Superuser for accessing extension.

Please update us on it.

Thanks & Regards
Ge
*o*