def combine(self):
aliases = None<EOL>if self.config.paths:<EOL><INDENT>aliases = PathAliases(self.file_locator)<EOL>for paths in self.config.paths.values():<EOL><INDENT>result = paths[<NUM_LIT:0>]<EOL>for pattern in paths[<NUM_LIT:1>:]:<EOL><INDENT>aliases.add(pattern, result)<EOL><DEDENT><DEDENT><DEDENT>self.data.combine_parallel_data(aliases=aliases)<EOL>
Combine together a number of similarly-named coverage data files.

        All coverage data files whose name starts with `data_file` (from the
        coverage() constructor) will be read, and combined together into the
        current measurements.