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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 extension(names):
 """Makes a function to be an extension."""

    for name in names:
        if not NAME_PATTERN.match(name):
            raise ValueError('invalid extension name: %s' % name)
    def decorator(f, names=names):
        return Extension(f, names=names)
    return decorator