code: func (c *KeyService) Create(ctx context.Context, data url.Values) (*Key, error) {
  	key := new(Key)
  	err := c.client.CreateResource(ctx, keyPathPart, data, key)
  	return key, err
  }
docs: // Create a new Key. Note the Secret is only returned in response to a Create,
  // you can't retrieve it later.
  //
  // https://www.twilio.com/docs/api/rest/keys#list-post