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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 linked_attribute(self):
 """Choose the Linkage attribute between `via` and designated `id_field` of the target class This method is initially called from `__set_name__()` -> `get_attribute_name()` at which point, the `to_cls` has not been initialized properly. We simply default the linked attribute to 'id' in that case. Eventually, when setting value the first time, the `to_cls` entity is initialized and the attribute name is reset correctly. """

        if isinstance(self.to_cls, str):
            return 'id'
        else:
            return self.via or self.to_cls.meta_.id_field.attribute_name