code: def element_style(attrs, style_def, parent_style):
      
      style = parent_style.copy()
      if 'class' in attrs:
          for css_class in attrs['class'].split():
              css_style = style_def['.' + css_class]
              style.update(css_style)
      if 'style' in attrs:
          immediate_style = dumb_property_dict(attrs['style'])
          style.update(immediate_style)
      return style
docs: returns a hash of the 'final' style attributes of the element