code: def write_node(self, a, **attrs):
          "a [a1=x,a2=y];"
          with self.rule():
              nodename = self._nodename(a)
              self.write(nodename)
              self._delattr(attrs, 'label', nodename)
              self._delattr(attrs, 'fillcolor', self.fillcolor)
              self._delattr(attrs, 'fontcolor', self.fontcolor)
              self.write_attributes(attrsf write_node(self, a, **attrs):
          "a [a1=x,a2=y];"
          with self.rule():
              nodename = self._nodename(a)
              self.write(nodename)
              self._delattr(attrs, 'label', nodename)
              self._delattr(attrs, 'fillcolor', self.fillcolor)
              self._delattr(attrs, 'fontcolor', self.fontcolor)
              self.write_attributes(attrs)
docs: a [a1=x,a2=y];