Parse this person name:

Siem van der Maath, 1399-1465, flourished 1424-1445
user
first_name: Siem
last_name: van der Maath
middle_names: []
temporal:
- start: 1399
  end: 1465
  type: life_span
- start: 1424
  end: 1445
  type: flourished
titles: []
extra_info: []
assistant