code: func (n *Network) WritePeerConfig(p *Peer, config *fabricconfig.Core) {
  	coreBytes, err := yaml.Marshal(config)
  	Expect(err).NotTo(HaveOccurred())
  
  	err = ioutil.WriteFile(n.PeerConfigPath(p), coreBytes, 0644)
  	Expect(err).NotTo(HaveOccurred())
  }
docs: // WritePeerConfig serializes the provided configuration as the specified
  // peer's core.yaml document.