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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 input(self, _in, out, **kw):
 """Input filtering."""

        args = [self.binary or 'cleancss'] + self.rebase_opt
        if self.extra_args:
            args.extend(self.extra_args)
        self.subprocess(args, out, _in)