docs: def unassign_proficiency_from_objective_bank(self, proficiency_id, objective_bank_id):
          """Removes a ``Proficiency`` from a ``ObjectiveBank``.
  
          arg:    proficiency_id (osid.id.Id): the ``Id`` of the
                  ``Proficiency``
          arg:    objective_bank_id (osid.id.Id): the ``Id`` of the
                  ``ObjectiveBank``
          raise:  NotFound - ``proficiency_id`` or ``objective_bank_id``
                  not found or ``proficiency_id`` not mapped to
                  ``objective_bank_id``
          raise:  NullArgument - ``proficiency_id`` or
                  ``objective_bank_id`` is ``null``
          raise:  OperationFailed - unable to complete request
          raise:  PermissionDenied - authorization failure
          *compliance: mandatory -- This method must be implemented.*
  
          """
          # Implemented from template for
          # osid.resource.ResourceBinAssignmentSession.unassign_resource_from_bin
          mgr = self._get_provider_manager('LEARNING', local=True)
          lookup_session = mgr.get_objective_bank_lookup_session(proxy=self._proxy)
          lookup_session.get_objective_bank(objective_bank_id)  # to raise NotFound
          self._unassign_object_from_catalog(proficiency_id, objective_bank_id)