title: module 'h5py' has no attribute 'string_dtype'
body: <p>I am trying to save a string in python 3.7. In the h5py documentation page it is all about data types such as this one:</p>
  
  <pre><code>dt = h5py.string_dtype(encoding='ascii')
  </code></pre>
  
  <p>But, when I try it, I get the following error.</p>
  
  <pre><code>module 'h5py' has no attribute 'string_dtype'
  </code></pre>
  
  <p>What is the easiest way to save strings into hdf5 format.</p>
  
  <p>Thank you</p>