docs: def update_repository(self, repository_form=None):
          """Updates an existing repository.
  
          arg:    repository_form (osid.repository.RepositoryForm): the
                  form containing the elements to be updated
          raise:  IllegalState - ``repository_form`` already used in an
                  update transaction
          raise:  InvalidArgument - the form contains an invalid value
          raise:  NullArgument - ``repository_form`` is ``null``
          raise:  OperationFailed - unable to complete request
          raise:  PermissionDenied - authorization failure
          raise:  Unsupported - ``repository_form`` did not originate from
                  ``get_repository_form_for_update()``
          *compliance: mandatory -- This method must be implemented.*
  
          """
          # Implemented from awsosid template for -
          # osid.resource.BinAdminSession.update_bin_template
          if not self._can('update'):
              raise PermissionDenied()
          else:
              return self._provider_session.update_repository(repository_form)