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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 process_file(self, path, dryrun):
 """ Concat files and return filename. """

        # special case - skip output file so we won't include it in result
        if path == self._output_path:
            return None

        # if dryrun skip and return file
        if dryrun:
            return path

        # concat file with output file
        with open(path, "rb") as infile:
            data = infile.read()
            self._output_file.write(data)

        # return processed file path
        return path