title: Using string labels in Tensorflow
body: <p>i'am still trying to run Tensorflow with own image data. 
  I was able to create a .tfrecords file with the conevert_to() function from this example <a href="https://tensorflow.googlesource.com/tensorflow/+/master/tensorflow/g3doc/how_tos/reading_data/convert_to_records.py" rel="noreferrer">link</a></p>
  
  <p>Now i i'd like to train the network with code from that example <a href="https://tensorflow.googlesource.com/tensorflow/+/master/tensorflow/g3doc/how_tos/reading_data/fully_connected_reader.py" rel="noreferrer">link</a>. </p>
  
  <p>But it fails in the read_and_decode() function. My changes in that function are:</p>
  
  <pre><code>label = tf.decode_raw(features['label'], tf.string) 
  </code></pre>
  
  <p>The Error is:</p>
  
  <pre><code>TypeError: DataType string for attr 'out_type' not in list of allowed values: float32, float64, int32, uint8, int16, int8, int64
  </code></pre>
  
  <p>So how to 1) read and 2) use string labels for training in tensorflow.</p>