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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 _merge_files(self, input_files, output_file):
 """Combine the input files to a big output file"""

        # we assume that all the input files have the same charset
        with open(output_file, mode='wb') as out:
            for input_file in input_files:
                out.write(open(input_file, mode='rb').read())