title: Is Pandas DataFrame df.loc a view or a new DataFrame object?
body: <p>Title says it. In the accepted answer to <a href="https://stackoverflow.com/questions/34884536/what-is-the-point-of-views-in-pandas-if-it-is-undefined-whether-an-indexing-oper">StackOverflow 34884536</a> it says</p>
  
  <blockquote>
    <p>You can find a longer discussion of the nature of the problem here,
    but the main take-away is that we're now moving to a "copy-on-write"
    behavior in which any time you slice, you get a new copy, and you
    never have to think about views.</p>
    
    <p>...</p>
    
    <p>Best guess is the fix will be in within a year -- in the mean time,
    I'm afraid some .copy() may be necessary, sorry!</p>
    
    <p>(answered 2016/01/20)</p>
  </blockquote>
  
  <p>Does df.loc[] return a 'copy' now? Or to be safe do I still have to use .copy()?</p>