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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 _check_journals_and_maybe_raise(self):
        '''Check if any journal files exist and raise an error.'''
        files = list(glob.glob(self._prefix_filename + '*-wpullinc'))

        if files:
            raise OSError('WARC file {} is incomplete.'.format(files[0]))