title: NumPy dtype issues in genfromtxt(), reads string in as bytestring
body: <p>I want to read in a standard-ascii csv file into numpy, which consists of floats and strings.</p>
  
  <p>E.g.,</p>
  
  <pre><code>ZINC00043096,C.3,C1,-0.1540,methyl
  ZINC00043096,C.3,C2,0.0638,methylene
  ZINC00043096,C.3,C4,0.0669,methylene
  ZINC00090377,C.3,C7,0.2070,methylene
  ...
  </code></pre>
  
  <p>Whatever I tried, the resulting array would look like</p>
  
  <p>E.g., </p>
  
  <pre><code>all_data = np.genfromtxt(csv_file, dtype=None, delimiter=',')
  
  
  [(b'ZINC00043096', b'C.3', b'C1', -0.154, b'methyl')
   (b'ZINC00043096', b'C.3', b'C2', 0.0638, b'methylene')
   (b'ZINC00043096', b'C.3', b'C4', 0.0669, b'methylene')
  </code></pre>
  
  <p>However, I want to save a step for the byte-string conversion and was wondering how I can read in the string columns as regular string directly.</p>
  
  <p>I tried several things from the numpy.genfromtxt() documentation, e.g., <code>dtype='S,S,S,f,S'</code> or <code>dtype='a25,a25,a25,f,a25'</code>, but nothing really helped here. </p>
  
  <p>I am afraid, but I think I just don't understand how the dtype conversion really works...Would be nice if you can give me some hint here!</p>
  
  <p>Thanks</p>