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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 import_powerflow_results(self, session):
 """Assign results from power flow analysis to edges and nodes Parameters session: :sqlalchemy:`SQLAlchemy session object<orm/session_basics.html>` Description """


        # bus data
        pypsa_io.import_pfa_bus_results(session, self)

        # line data
        pypsa_io.import_pfa_line_results(session, self)