Determine whether to forward client REQUESTs to replicas, based on the
        following logic:

        - If exactly f+1 PROPAGATE requests are received, then forward.
        - If less than f+1 of requests then probably there's no consensus on the
            REQUEST, don't forward.
        - If more than f+1 then already forwarded to replicas, don't forward

        Even if the node hasn't received the client REQUEST itself, if it has
        received enough number of PROPAGATE messages for the same, the REQUEST
        can be forwarded.

        :param request: the client REQUEST

def canForward(self, request: Request):
        """
        Determine whether to forward client REQUESTs to replicas, based on the
        following logic:

        - If exactly f+1 PROPAGATE requests are received, then forward.
        - If less than f+1 of requests then probably there's no consensus on the
            REQUEST, don't forward.
        - If more than f+1 then already forwarded to replicas, don't forward

        Even if the node hasn't received the client REQUEST itself, if it has
        received enough number of PROPAGATE messages for the same, the REQUEST
        can be forwarded.

        :param request: the client REQUEST
        """

        if self.requests.forwarded(request):
            return 'already forwarded'

        # If not enough Propagates, don't bother comparing
        if not self.quorums.propagate.is_reached(self.requests.votes(request)):
            return 'not finalised'

        req = self.requests.req_with_acceptable_quorum(request,
                                                       self.quorums.propagate)
        if req:
            self.requests.set_finalised(req)
            return None
        else:
            return 'not finalised'