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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 tonativefunc(enc='utf-8'):
    ''' Returns a function that turns everything into 'native' strings using enc '''
    if sys.version_info >= (3,0,0):
        return lambda x: x.decode(enc) if isinstance(x, bytes) else str(x)
    return lambda x: x.encode(enc) if isinstance(x, unicode) else str(x)