docs: def to_dictionary(self):
          """Serialize an object into dictionary form.  Useful if you have to
          serialize an array of objects into JSON.  Otherwise, if you call the
          :meth:`to_json` method on each object in the list and then try to
          dump the array, you end up with an array with one string."""
  
          j = {}
          j['interval'] = {'start': self.start.isoformat(),
                           'end': self.end.isoformat()}
          j['found'] = {'v': self.v, 't': self.t.isoformat()}
          return j