def LoadStyleSheet(self, name):
    if name in self.loaded_style_sheets:
      return self.loaded_style_sheets[name]

    resource = self._FindResourceGivenNameAndSuffix(
        name, '.css', return_resource=True)
    if not resource:
      raise module.DepsException(
          'Could not find a file for stylesheet %s' % name)

    style_sheet = style_sheet_module.StyleSheet(self, name, resource)
    style_sheet.load()
    self.loaded_style_sheets[name] = style_sheet
    return style_sheet