code: def fmt(self, fills):
          
          f = "%(tab)s%(property)s:%(ws)s%(style)s%(important)s;%(nl)s"
          imp = ' !important' if self.important else ''
          if fills['nl']:
              self.parsed = [
                  ',%s' % fills['ws'] if p == ',' else p for p in self.parsed
              ]
          style = ''.join([
              p.fmt(fills) if hasattr(p, 'fmt') else str(p) for p in self.parsed
          ])
          # IE cannot handle no space after url()
          style = re.sub("(url\([^\)]*\))([^\s,])", "\\1 \\2", style)
          fills.update({
              'property': self.property,
              'style': style.strip(),
              'important': imp
          })
          return f % fills
docs: Format node
          args:
              fills (dict): replacements
          returns:
              str