title: How to get np.char.add() to put a space between the concatenated strings
body: <p>I need a space between the strings that are concatenated by np.char.add()</p>
  <pre><code>import numpy as np
  arr1 = np.array(['Indiana', 'Cincinnati', 'Purdue', 'Ball State'], dtype=np.str)
  arr2 = np.array(['Hoosiers', 'Bearcats','Boilermakers', 'Cardinals'], dtype=np.str)
  teams = np.char.add(arr1, arr2)
  print(teams)
  </code></pre>
  <p>and I get this:</p>
  <pre><code>['IndianaHoosiers' 'CincinnatiBearcats' 'PurdueBoilermakers'
   'Ball StateCardinals']
  </code></pre>
  <p>I need this:</p>
  <pre><code>['Indiana Hoosiers' 'Cincinnati Bearcats' 'Purdue Boilermakers'
   'Ball State Cardinals']
  </code></pre>