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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 _get_sample(self, mode, encoding):
 """ Get a sample from the next current input file. :param str mode: The mode for opening the file. :param str|None encoding: The encoding of the file. None for open the file in binary mode. """

        self._open_file(mode, encoding)
        self._sample = self._file.read(UniversalCsvReader.sample_size)
        self._file.close()