@classmethod
def remove_item(cls, i):
    """Remove the specified item from this list. Called by
        :meth:`Choice.remove`.
        """
    del cls.items_dict[i.value]
    for name in i.names:
        cls.removed_names.add(name)
        delattr(cls, name)
    for n, el in enumerate(cls.choices):
        if el[0] == i:
            del cls.choices[n]
    for n, a in enumerate(cls.workflow_actions):
        if a.target_state == i:
            del cls.workflow_actions[n]
