docs: def _update_style(self):
          """ Sets the style to the specified Pygments style.
          """
          try:
              self._style = get_style_by_name(self._pygments_style)
          except ClassNotFound:
              # unknown style, also happen with plugins style when used from a
              # frozen app.
              if self._pygments_style == 'qt':
                  from pyqode.core.styles import QtStyle
                  self._style = QtStyle
              elif self._pygments_style == 'darcula':
                  from pyqode.core.styles import DarculaStyle
                  self._style = DarculaStyle
              else:
                  self._style = get_style_by_name('default')
                  self._pygments_style = 'default'
          self._clear_caches()