docs: function checkCertificate() {
      return certificates.listCertificates({
          filter: {
              type: "developer"
          }
      })
      .then(certs => {
          var certificate = certs.data.find(cert => {
              return cert.name === certificateName;
          });
  
          if (certificate) {
              return new Promise((resolve, reject) => {
                  var rl = readline.createInterface({
                      input: process.stdin,
                      output: process.stdout
                  });
  
                  rl.question("Developer certificate already exists, overwrite? [y/N] ", answer => {
                      rl.close();
                      if (answer === "y") {
                          return certificate.delete()
                          .then(() => {
                              resolve();
                          });
                      } else {
                          reject();
                      }
                  });
              });
          }
      });
  }