def start(<EOL>self, resource_group_name, vm_scale_set_name, instance_ids=None, custom_headers=None, raw=False, polling=True, **operation_config):
raw_result = self._start_initial(<EOL>resource_group_name=resource_group_name,<EOL>vm_scale_set_name=vm_scale_set_name,<EOL>instance_ids=instance_ids,<EOL>custom_headers=custom_headers,<EOL>raw=True,<EOL>**operation_config<EOL>)<EOL>def get_long_running_output(response):<EOL><INDENT>deserialized = self._deserialize('<STR_LIT>', response)<EOL>if raw:<EOL><INDENT>client_raw_response = ClientRawResponse(deserialized, response)<EOL>return client_raw_response<EOL><DEDENT>return deserialized<EOL><DEDENT>lro_delay = operation_config.get(<EOL>'<STR_LIT>',<EOL>self.config.long_running_operation_timeout)<EOL>if polling is True: polling_method = ARMPolling(lro_delay, lro_options={'<STR_LIT>': '<STR_LIT>'}, **operation_config)<EOL>elif polling is False: polling_method = NoPolling()<EOL>else: polling_method = polling<EOL>return LROPoller(self._client, raw_result, get_long_running_output, polling_method)<EOL>
Starts one or more virtual machines in a VM scale set.

        :param resource_group_name: The name of the resource group.
        :type resource_group_name: str
        :param vm_scale_set_name: The name of the VM scale set.
        :type vm_scale_set_name: str
        :param instance_ids: The virtual machine scale set instance ids.
         Omitting the virtual machine scale set instance ids will result in the
         operation being performed on all virtual machines in the virtual
         machine scale set.
        :type instance_ids: list[str]
        :param dict custom_headers: headers that will be added to the request
        :param bool raw: The poller return type is ClientRawResponse, the
         direct response alongside the deserialized response
        :param polling: True for ARMPolling, False for no polling, or a
         polling object for personal polling strategy
        :return: An instance of LROPoller that returns OperationStatusResponse
         or ClientRawResponse<OperationStatusResponse> if raw==True
        :rtype:
         ~msrestazure.azure_operation.AzureOperationPoller[~azure.mgmt.compute.v2017_12_01.models.OperationStatusResponse]
         or
         ~msrestazure.azure_operation.AzureOperationPoller[~msrest.pipeline.ClientRawResponse[~azure.mgmt.compute.v2017_12_01.models.OperationStatusResponse]]
        :raises: :class:`CloudError<msrestazure.azure_exceptions.CloudError>`