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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_auth(func):
 """Decorator function to check authorization header. Usage example: @check_auth def do_PUT_foo():
 pass """

    def wrapper(handler, *args, **kwargs):
        if handler.check_auth_header():
            return func(handler, *args, **kwargs)
    return wrapper