Biodegradable polyphosphazene polymers containing pyrrolidone side groups, and the biomedical use of such polyphosphazene polymers are disclosed. Further, the extrusion molded article can be molded with high accuracy by extracting the aluminum alloy after extrusion. The second stage fiber is arranged as a plug-in module which connects between a first stage isolator and a mid-stage loss between the second and third stages. The ratio of the accelerator to sulfur or peroxide ranges from 1:4 to 1:10 depending on the activity of the peroxide. Based on the inter-replica and inter-data correlation, the selected proper subset of replicas is indexed to generate a unified content index.