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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 wrap(self, data):
 """Wrap this with the root schema definitions."""

        if self.nested:  # no need to wrap, will be in outer defs
            return data

        name = self.obj.__class__.__name__
        self._nested_schema_classes[name] = data
        root = {
            'definitions': self._nested_schema_classes,
            '$ref': '#/definitions/{name}'.format(name=name)
        }
        return root