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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 add(self, value):
 """Create a safe directory from a value."""

        path = value if isinstance(value, Path) else Path(str(value))
        if path and path != path.parent:
            destination = self
            for part in path.parts:
                destination = destination.setdefault(part, DirectoryTree())