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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_parent_element(self):
 """Signatures and Audit elements share sub-elements, we need to know which to set attributes on"""

        return {AUDIT_REF_STATE: self.context.audit_record,
                SIGNATURE_REF_STATE: self.context.signature}[self.ref_state]