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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add_permissions(self, grp_name, resource, permissions):
 """ Add additional permissions for the group associated with the given resource. Args: grp_name (string):
 Name of group. resource (intern.resource.boss.BossResource):
 Identifies which data model object to operate on. permissions (list):
 List of permissions to add to the given resource. Raises: requests.HTTPError on failure. """

        self.service.add_permissions(
            grp_name, resource, permissions,
            self.url_prefix, self.auth, self.session, self.session_send_opts)