    def process_view(self, request, callback, callback_args, callback_kwargs):
        if getattr(request, "csrf_processing_done", False):
            return None

        # Wait until request.META["CSRF_COOKIE"] has been manipulated before
        # bailing out, so that get_token still works
        if getattr(callback, "csrf_exempt", False):
            return None

        # Assume that anything not defined as 'safe' by RFC 9110 needs
        # protection
        if request.method in ("GET", "HEAD", "OPTIONS", "TRACE"):
            return self._accept(request)

        if getattr(request, "_dont_enforce_csrf_checks", False):
…
            return self._accept(request)

        # Reject the request if the Origin header doesn't match an allowed
        # value.
        if "HTTP_ORIGIN" in request.META:
            if not self._origin_verified(request):
                return self._reject(
                    request, REASON_BAD_ORIGIN % request.META["HTTP_ORIGIN"]
                )
        elif request.is_secure():
            # If the Origin header wasn't provided, reject HTTPS requests if
            # the Referer header doesn't match an allowed value.
…
            try:
                self._check_referer(request)
            except RejectRequest as exc:
                return self._reject(request, exc.reason)

        try:
            self._check_token(request)
        except RejectRequest as exc:
            return self._reject(request, exc.reason)

        return self._accept(request)

Échauffement