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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def output_extras(self, output_file):
 """ Returns dict mapping local path to remote name. """

        output_directory = dirname(output_file)

        def local_path(name):
            return join(output_directory, self.path_helper.local_name(name))

        files_directory = "%s_files%s" % (basename(output_file)[0:-len(".dat")], self.path_helper.separator)
        names = filter(lambda o: o.startswith(files_directory), self.output_directory_contents)
        return dict(map(lambda name: (local_path(name), name), names))