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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 subscribe(self, feedUrl):
 """ Adds a feed to the top-level subscription list Ubscribing seems idempotent, you can subscribe multiple times without error returns True or throws HTTPError """

        response = self.httpPost(
            ReaderUrl.SUBSCRIPTION_EDIT_URL,
            {'ac':'subscribe', 's': feedUrl})
        # FIXME - need better return API
        if response and 'OK' in response:
            return True
        else:
            return False