code: def _load(self):
          
          # loop over system path
          if self._loaded:
              return
          icon_paths = ['/usr/local/share/meqtrees'] + sys.path
          for path in icon_paths:
              path = path or '.'
              # for each entry, try <entry>/icons/<appname>'
              for a, b in [('icons', self._appname), (self._appname, 'icons')]:
                  trydir = os.path.join(path, a, b)
                  _dprint(3, 'trying icon path', trydir)
                  try:
                      files = os.listdir(trydir)
                  except:
                      continue
                  _dprint(3, len(files), 'entries in', trydir)
                  # loop over all files
                  nicons = 0
                  for f in files:
                      (name, ext) = os.path.splitext(f);  # check extension
                      if ext in ('.png', '.xpm', '.gif'):
                          f = os.path.join(trydir, f)
                          try:
                              pm = QPixmap(f)
                          except:
                              _dprint(3, 'error loading icon', name, sys.exc_value())
                              continue
                          # register pixmap
                          self._pixmaps[name] = QPixmapWrapper(pm)
                          nicons += 1
                          _dprint(4, 'loaded icon', f)
                      else:
                          _dprint(4, 'ignoring entry', f)
                  _dprint(1, nicons, 'icons loaded from ', trydir)
                  self._loaded = True
docs: load all icons found in path, subdirs 'icons/appname