ingestion.py

department_map = {}
reader = csvreaderitems

def get_or_create_department(department_id):
    department = department_map.get(department_id, None)
    if department is None:
        department = Department.create(id=department_id)
        department_map[department_id] = department
    return department

for entry in reader:
    d = get_or_create_department(entry['manager tier 6'])
    employee = Employee.create(name=entry['name'], department=d)