@cached_property<EOL><INDENT>def cost(self):<DEDENT>
total = <NUM_LIT:0.0><EOL>for family, rules in self._excludes.iteritems():<EOL><INDENT>cost = sum(x.cost() for x in rules)<EOL>if family:<EOL><INDENT>cost = cost / float(<NUM_LIT:10>)<EOL><DEDENT>total += cost<EOL><DEDENT>return total<EOL>
Get the approximate cost of this filter.

        Cost is the total cost of the exclusion rules in this filter. The cost
        of family-specific filters is divided by 10.

        Returns:
            float: The approximate cost of the filter.