code: def match(self, item):
          
          if 0 and getattr(item, self._name):
              print "%r %r %r %r %r %r" % (self._cmp(float(getattr(item, self._name)), self._value),
                    self._name, self._condition, item.name, getattr(item, self._name), self._value)
          val = getattr(item, self._name) or 0
          if self.not_null and self._value and not val:
              return False
          else:
              return self._cmp(float(val), self._value)
docs: Return True if filter matches item.