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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 postprocess(self, tempname, filename):
 """Perform any platform-specific postprocessing of `tempname` This is where Mac header rewrites should be done; other platforms don't have anything special they should do. Resource providers should call this method ONLY after successfully extracting a compressed resource. They must NOT call it on resources that are already in the filesystem. `tempname` is the current (temporary) name of the file, and `filename` is the name it will be renamed to by the caller after this routine returns. """


        if os.name == 'posix':
            # Make the resource executable
            mode = ((os.stat(tempname).st_mode) | 0o555) & 0o7777
            os.chmod(tempname, mode)