def remove_user_role(self, user_role):
        """
        Remove the specified User Role from this User.

        This User must not be a system-defined or pattern-based user.

        Authorization requirements:

        * Task permission to the "Manage Users" task to modify a standard user
          or the "Manage User Templates" task to modify a template user.

        Parameters:

          user_role (:class:`~zhmcclient.UserRole`): User Role to be removed.
            Must not be `None`.

        Raises:

          :exc:`~zhmcclient.HTTPError`
          :exc:`~zhmcclient.ParseError`
          :exc:`~zhmcclient.AuthError`
          :exc:`~zhmcclient.ConnectionError`
        """
        body = {
            'user-role-uri': user_role.uri
        }
        self.manager.session.post(
            self.uri + '/operations/remove-user-role',
            body=body)