code: def mergeStyles(self, styles):
          " XXX Bugfix for use in PISA "
          for k, v in six.iteritems(styles):
              if k in self and self[k]:
                  self[k] = copy.copy(self[k])
                  self[k].update(v)
              else:
                  self[k] = f mergeStyles(self, styles):
          " XXX Bugfix for use in PISA "
          for k, v in six.iteritems(styles):
              if k in self and self[k]:
                  self[k] = copy.copy(self[k])
                  self[k].update(v)
              else:
                  self[k] = v
docs: XXX Bugfix for use in PISA