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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 _get_real_ip(self):
 """ Get IP from request. :param request: A usual request object :type request: HttpRequest :return: ipv4 string or None """

        try:
            # Trying to work with most common proxy headers
            real_ip = self.request.META['HTTP_X_FORWARDED_FOR']
            return real_ip.split(',')[0]
        except KeyError:
            return self.request.META['REMOTE_ADDR']
        except Exception:
            # Unknown IP
            return None