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 = {}
          for p in self.properties:
              try:
                  v = getattr(self, p)
              except AttributeError:
                  continue
              if v is not None:
                  if p == 't':
                      j[p] = getattr(self, p).isoformat()
                  else:
                      j[p] = getattr(self, p)
  
          return j