Scenario
Feasibility of using a single CSV file for importing various types of records into NetSuite using task module in scheduled script
Created a scheduled script.
Created 2 Saved imports, one for customers and the other for items.

Saved a CSV file in suitescript folder under the name testcsvimport.csv
The sample is given below

Script used to import
function executeschedule(context) {
try {
log.debug("Script triggered", "Script triggered")
let scriptTask1 = task.create({ taskType: task.TaskType.CSV_IMPORT });
scriptTask1.mappingId = 'custimport_1_t2782962_140'
let f = file.load('SuiteScripts/testcsvimport.csv');
scriptTask1.importFile = f;
let id1 = scriptTask1.submit();
log.debug("id1", id1);
let scriptTask2 = task.create({ taskType: task.TaskType.CSV_IMPORT });
scriptTask2.mappingId = 'custimport_jj_test_csv_import';
scriptTask2.importFile = f;
let id2 = scriptTask2.submit();
log.debug("id2", id2);
} catch (error) {
log.error("Error @executeschedule", error);
}
}