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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_all(self, search_filter=None):
 """Fetch all data from backend."""

        items = self.backend.get_all()

        if not items:
            if self.version == 1:
                return {self.namespace: []}
            return []

        if search_filter:
            items = jmespath.search(search_filter, items)

        return items