How to use the synthetix.getSynths function in synthetix

Object.values(SUPPORTED_NETWORKS).map(network => {
    // add the synth contract as well (target addresses are their proxies, and source is the synth contract)
    const synthContracts = snx.getSynths({ network }).reduce((memo, { name, subclass }) => {
      memo[name] = { target: `Proxy${name}`, source: subclass || 'Synth' };
      return memo;
    }, {});

    const allContracts = Object.assign({}, contracts, synthContracts);

    const importStringForHeaders = `import ${network} from './${network}';`;
    indexFileHeader.push(importStringForHeaders);

    const srcNetworkIndexFileHeader = [];
    const abiNetworkIndexFileHeader = [];
    const contractsInNetwork = [];
    const sourcesInNetwork = [];
    Object.keys(allContracts).forEach(contractName => {
      let target = contractName;
      let source = contractName;

.map(network => {
      const synths = snx.getSynths({ network });

      return `
        const ${network.toUpperCase()}_SYNTHS = ${util.inspect(synths, {
        showHidden: false,
        depth: null,
      })}
        `;
    })
    .join('\n\n');