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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_next_file_path(self, service, operation):
 """ Returns a tuple with the next file to read and the serializer format used """

        base_name = '{0}.{1}'.format(service, operation)
        if self.prefix:
            base_name = '{0}.{1}'.format(self.prefix, base_name)
        LOG.debug('get_next_file_path: %s', base_name)
        next_file = None
        serializer_format = None
        index = self._index.setdefault(base_name, 1)

        while not next_file:
            file_name = os.path.join(
                self._data_path, base_name + '_{0}'.format(index))
            next_file, serializer_format = self.find_file_format(file_name)
            if next_file:
                self._index[base_name] += 1
            elif index != 1:
                index = 1
                self._index[base_name] = 1
            else:
                raise IOError('response file ({0}.[{1}]) not found'.format(
                    file_name, "|".join(Format.ALLOWED)))

        return next_file, serializer_format