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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 init(self, request, paypal_request, paypal_response):
 """Initialize a PayPalNVP instance from a HttpRequest."""

        if request is not None:
            from paypal.pro.helpers import strip_ip_port
            self.ipaddress = strip_ip_port(request.META.get('REMOTE_ADDR', ''))
            if (hasattr(request, "user") and request.user.is_authenticated):
                self.user = request.user
        else:
            self.ipaddress = ''

        # No storing credit card info.
        query_data = dict((k, v) for k, v in paypal_request.items() if k not in self.RESTRICTED_FIELDS)
        self.query = urlencode(query_data)
        self.response = urlencode(paypal_response)

        # Was there a flag on the play?
        ack = paypal_response.get('ack', False)
        if ack != "Success":
            if ack == "SuccessWithWarning":
                warn_untested()
                self.flag_info = paypal_response.get('l_longmessage0', '')
            else:
                self.set_flag(paypal_response.get('l_longmessage0', ''), paypal_response.get('l_errorcode', ''))