json no indent
data.cls.Pron supports "==" operation
next is a builtin function
data.cls.Char
cls.Char.pron -> cls.Char.prons
cls.Char.prons is set of Pron instead of str
cls.data.Pron inherits namedtuple()
cls.data.Pron becomes hashable
cls.data.Pron becomes immutable
name fixes