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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def tuple_sealer(fields, defaults):
 """ This sealer returns an equivalent of a ``namedtuple``. """

    baseclass_name = 'FieldsBase_for__{0}'.format('__'.join(fields))
    global_namespace, local_namespace = make_init_func(
        fields, defaults, baseclass_name,
        header_name='__new__',
        header_start='def {func_name}(cls',
        header_end='):\n',
        super_call_start='return tuple.__new__(cls, (',
        super_call_end='))\n',
        super_call_pass_kwargs=False, set_attributes=False,
    )

    def __getnewargs__(self):
        return tuple(self)

    def __repr__(self):
        return "{0}({1})".format(
            self.__class__.__name__,
            ", ".join(a + "=" + repr(getattr(self, a)) for a in fields)
        )

    return type(baseclass_name, (tuple,), dict(
        [(name, property(itemgetter(i))) for i, name in enumerate(fields)],
        __new__=local_namespace['__new__'],
        __getnewargs__=__getnewargs__,
        __repr__=__repr__,
        __slots__=(),
    ))