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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 map_vp(self, port1, vpi1, port2, vpi2):
 """ Creates a new Virtual Path connection. :param port1: input port :param vpi1: input vpi :param port2: output port :param vpi2: output vpi """


        if port1 not in self._nios:
            return

        if port2 not in self._nios:
            return

        nio1 = self._nios[port1]
        nio2 = self._nios[port2]

        yield from self._hypervisor.send('atmsw create_vpc "{name}" {input_nio} {input_vpi} {output_nio} {output_vpi}'.format(name=self._name,
                                                                                                                              input_nio=nio1,
                                                                                                                              input_vpi=vpi1,
                                                                                                                              output_nio=nio2,
                                                                                                                              output_vpi=vpi2))

        log.info('ATM switch "{name}" [{id}]: VPC from port {port1} VPI {vpi1} to port {port2} VPI {vpi2} created'.format(name=self._name,
                                                                                                                          id=self._id,
                                                                                                                          port1=port1,
                                                                                                                          vpi1=vpi1,
                                                                                                                          port2=port2,
                                                                                                                          vpi2=vpi2))

        self._active_mappings[(port1, vpi1)] = (port2, vpi2)