Process JSON data found in the response.

def proc_response(self, resp):
        """Process JSON data found in the response."""

        # Try to interpret any JSON
        try:
            resp.obj = json.loads(resp.body)
            self._debug("  Received entity: %r", resp.obj)
        except ValueError:
            resp.obj = None
            self._debug("  No received entity; body %r", resp.body)

        # Now, call superclass method for error handling
        super(JSONRequest, self).proc_response(resp)