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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 _traverse(self, name, create_missing=False, action=None, value=NO_DEFAULT):
 """Traverse to the item specified by ``name``. To create missing items on the way to the ``name``d item, pass ``create_missing=True``. This will insert an item for each missing segment in ``name``. The type and value of item that will be inserted for a missing segment depends on the *next* segment. If a ``default`` value is passed, the ``name``d item will be set to this value; otherwise, a default default will be used. See :meth:`_create_segment` for more info. """

        obj = self
        segments = self._parse_path(name)

        for segment, next_segment in zip(segments, segments[1:] + [None]):
            last = next_segment is None

            if create_missing:
                self._create_segment(obj, segment, next_segment)

            try:
                next_obj = obj[segment]
            except IndexError:
                raise KeyError(segment)

            if not last:
                obj = next_obj
            else:
                if action:
                    value = action(obj, segment)
                elif value is not NO_DEFAULT:
                    obj[segment] = value
                else:
                    value = obj[segment]

        return value