How to use the synthetix.getSource function in synthetix

Object.keys(allContracts).forEach(contractName => {
      let target = contractName;
      let source = contractName;
      if (typeof allContracts[contractName] === 'object') {
        target = allContracts[contractName].target || target;
        source = allContracts[contractName].source || source;
      }

      // get the abis from the network's deploy from synthetix
      const { abi } = snx.getSource({ network, contract: source }) || {};
      // some environments might not have an ABI for this contract yet
      if (abi) {
        // track which contracts exist in this netork
        contractsInNetwork.push(contractName);

        // now create import header for index files
        const importStringForIndexFile = `import ${contractName} from './${contractName}';`;
        srcNetworkIndexFileHeader.push(importStringForIndexFile);

        // now only for source contracts in the original contract object
        if (contractName in contracts) {
          // write out ABI files (using ABIs from mainnet deploy)
          writeABIFileAsJS(network, contractName, abi);
          abiNetworkIndexFileHeader.push(importStringForIndexFile);

          // and track it

() => {
            expect(snxjs[synth].contract.interface.abi).toEqual(
              snx.getSource({ network, contract }).abi
            );
          };
        });

const writeAllABIFiles = network => {
  const folder = path.join(__dirname, '..', 'lib', 'abis', network);
  if (!fs.existsSync(folder)) {
    fs.mkdirSync(folder);
  }
  const sources = snx.getSource({ network });

  for (const [source, { abi }] of Object.entries(sources)) {
    const abiPath = path.join(folder, `${source}.json`);
    fs.writeFile(abiPath, JSON.stringify(abi, null, '\t') + '\n', err => {
      if (err) {
        console.log(err);
      } else {
        console.log(`ABI ${source}.son on ${network} successfully generated locally.`);
      }
    });
  }
};