def __init__(self, id, title=None, references=None):
if not references: references = []
tk.assertType(str, id=id)
tk.assertType((str, None), title=title)
tk.assertType((list, tuple, None), references=references)
if references:
tk.assertTypeForAllIn(str, references)
self.id = tk.toStringFormattedCPE(id)
self.id_2_2 = tk.toOldCPE(id)
self.title = title if title else tk.cpeTitle(self.id)
self.references = references and list(references) or []
