def METHOD_NAME(eventType,source):
    import os
    requirements = ''
    for item in datasetDict[eventType].items():
        requirements += item[0]+' = '+item[1]+' and '
    requirements += 'release = %s' % os.environ['CMSSW_VERSION']
    foundDs = GetDbsInfo('dataset', requirements)
    selDs = ''
    if len(foundDs) > 1:
        print("Multiple datasets found for %s! Which one you would like to use?" % eventType)
        for ds in foundDs:
            print("%s  :  %s" % (foundDs.index(ds),ds))
        cnum = int(raw_input("\nselect Dataset: "))
        selDs = foundDs[cnum]
    elif len(foundDs) == 0:
        print("Sorry! No Dataset found, exiting...")
        return None
    else:
        selDs = foundDs[0]
    requirements = 'dataset = %s' % selDs
    files = GetDbsInfo('file', requirements)
    for entry in files:
        source.fileNames.append(entry)