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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 get(self, value, default=None):
 """Return a subtree if exists."""

        path = value if isinstance(value, Path) else Path(str(value))
        subtree = self
        for part in path.parts:
            try:
                subtree = subtree[part]
            except KeyError:
                return default
        return subtree