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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_output(*args, **kwargs):
    '''Compatibility wrapper for Python 2.6 missin g subprocess.check_output'''
    if hasattr(subprocess, 'check_output'):
        return subprocess.check_output(stderr=subprocess.STDOUT, universal_newlines=True,
                                       *args, **kwargs)
    else:
        process = subprocess.Popen(*args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT,
                                   universal_newlines=True, **kwargs)
        output, _ = process.communicate()
        retcode = process.poll()
        if retcode:
            error = subprocess.CalledProcessError(retcode, args[0])
            error.output = output
            raise error
        return output