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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 _Initialize(self, http, url):
 """Initialize this download by setting self.http and self.url. We want the user to be able to override self.http by having set the value in the constructor; in that case, we ignore the provided http. Args: http: An httplib2.Http instance or None. url: The url for this transfer. Returns: None. Initializes self. """

        self.EnsureUninitialized()
        if self.http is None:
            self.__http = http or http_wrapper.GetHttp()
        self.__url = url