 
    <section class="summary source-code" id="source">
      <h2><span>Implementation</span></h2>
      <pre class="language-dart"><code class="language-dart">int addInput(dynamic txHashOrInstance, int vout, [int sequence, Uint8List prevOutScript]) {
  assert(txHashOrInstance is String || txHashOrInstance is Uint8List || txHashOrInstance is Transaction);

  if (!_canModifyInputs()) {
    throw new ArgumentError(&#39;No, this would invalidate signatures&#39;);
  }
  Uint8List hash;
  var value;
  if (txHash