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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 as_allocate_quota_request(self, timer=datetime.utcnow):
 """Makes a `ServicecontrolServicesAllocateQuotaRequest` from this instance Returns: a ``ServicecontrolServicesAllocateQuotaRequest`` Raises: ValueError: if the fields in this instance are insufficient to to create a valid ``ServicecontrolServicesAllocateQuotaRequest`` """

        if not self.service_name:
            raise ValueError(u'the service name must be set')
        if not self.operation_id:
            raise ValueError(u'the operation id must be set')
        if not self.operation_name:
            raise ValueError(u'the operation name must be set')
        op = super(Info, self).as_operation(timer=timer)
        labels = {}
        if self.client_ip:
            labels[_KNOWN_LABELS.SCC_CALLER_IP.label_name] = self.client_ip

        if self.referer:
            labels[_KNOWN_LABELS.SCC_REFERER.label_name] = self.referer

        qop = sc_messages.QuotaOperation(
            operationId=op.operationId,
            methodName=op.operationName,
            consumerId=op.consumerId,
            quotaMode=sc_messages.QuotaOperation.QuotaModeValueValuesEnum.BEST_EFFORT,
        )
        qop.labels = encoding.PyValueToMessage(
            sc_messages.QuotaOperation.LabelsValue, labels)

        quota_info = self.quota_info if self.quota_info else {}
        qop.quotaMetrics = [
            sc_messages.MetricValueSet(
                metricName=name, metricValues=[sc_messages.MetricValue(int64Value=cost)])
            for name, cost in quota_info.items()
        ]

        allocate_quota_request = sc_messages.AllocateQuotaRequest(allocateOperation=qop)
        if self.config_id:
            allocate_quota_request.serviceConfigId = self.config_id
        return sc_messages.ServicecontrolServicesAllocateQuotaRequest(
            serviceName=self.service_name,
            allocateQuotaRequest=allocate_quota_request)