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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 update(self, request, *args, **kwargs):
 """Update one or more model instances. If ENABLE_BULK_UPDATE is set, multiple previously-fetched records may be updated in a single call, provided their IDs. If ENABLE_PATCH_ALL is set, multiple records may be updated in a single PATCH call, even without knowing their IDs. *WARNING*: ENABLE_PATCH_ALL should be considered an advanced feature and used with caution. This feature must be enabled at the viewset level and must also be requested explicitly by the client via the "patch-all" query parameter. This parameter can have one of the following values: true (or 1):
 records will be fetched and then updated in a transaction loop - The `Model.save` method will be called and model signals will run - This can be slow if there are too many signals or many records in the query - This is considered the more safe and default behavior query: records will be updated in a single query - The `QuerySet.update` method will be called and model signals will not run - This will be fast, but may break data constraints that are controlled by signals - This is considered unsafe but useful in certain situations The server's successful response to a patch-all request will NOT include any individual records. Instead, the response content will contain a "meta" object with an "updated" count of updated records. Examples: Update one dog: PATCH /dogs/1/ { 'fur': 'white' } Update many dogs by ID: PATCH /dogs/ [ {'id': 1, 'fur': 'white'}, {'id': 2, 'fur': 'black'}, {'id': 3, 'fur': 'yellow'} ] Update all dogs in a query: PATCH /dogs/?filter{fur.contains}=brown&patch-all=true { 'fur': 'gold' } """
  # noqa
        if self.ENABLE_BULK_UPDATE:
            patch_all = self.get_request_patch_all()
            if self.ENABLE_PATCH_ALL and patch_all:
                # patch-all update
                data = request.data
                return self._patch_all(
                    data,
                    query=(patch_all == 'query')
                )
            else:
                # bulk payload update
                partial = 'partial' in kwargs
                bulk_payload = self._get_bulk_payload(request)
                if bulk_payload:
                    return self._bulk_update(bulk_payload, partial)

        # singular update
        try:
            return super(DynamicModelViewSet, self).update(request, *args,
                                                           **kwargs)
        except AssertionError as e:
            err = str(e)
            if 'Fix your URL conf' in err:
                # this error is returned by DRF if a client
                # makes an update request (PUT or PATCH) without an ID
                # since DREST supports bulk updates with IDs contained in data,
                # we return a 400 instead of a 500 for this case,
                # as this is not considered a misconfiguration
                raise exceptions.ValidationError(err)
            else:
                raise