code: function (key) {
          // Call the super constructor.
          RSAKey.call(this);
          // If a key key was provided.
          if (key) {
              // If this is a string...
              if (typeof key === 'string') {
                  this.parseKey(key);
              }
              else if (
                  this.hasPrivateKeyProperty(key) ||
                  this.hasPublicKeyProperty(key)
              ) {
                  // Set the values for the key.
                  this.parsePropertiesFrom(key);
              }
          }
      }
docs: Create a new JSEncryptRSAKey that extends Tom Wu's RSA key object.
  This object is just a decorator for parsing the key parameter
  @param {string|Object} key - The key in string format, or an object containing
  the parameters needed to build a RSAKey object.
  @constructor