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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 digest_auth(realm, auth_func):
 """A decorator used to protect methods with HTTP Digest authentication. """

    def digest_auth_decorator(func):
        def func_replacement(self, *args, **kwargs):
            # 'self' here is the RequestHandler object, which is inheriting
            # from DigestAuthMixin to get 'get_authenticated_user'
            if self.get_authenticated_user(auth_func, realm):
                return func(self, *args, **kwargs)
        return func_replacement
    return digest_auth_decorator