code: function clone(input) {
    if (isStream(input)) {
      const teed = tee(input);
      overwrite(input, teed[0]);
      return teed[1];
    }
    return slice(input);
  }
docs: Clone a Stream for reading it twice. The input stream can still be read after clone()ing.
  Reading from the clone will pull from the input stream.
  The input stream will only be canceled if both the clone and the input stream are canceled.
  @param {ReadableStream|Uint8array|String} input
  @returns {ReadableStream|Uint8array|String} cloned input