Parse this person name:

Siem Nieuwstraten (1252-1323, flourished 1280-1294)
user
first_name: Siem
last_name: Nieuwstraten
middle_names: []
temporal:
- start: 1252
  end: 1323
  type: life_span
- start: 1280
  end: 1294
  type: flourished
titles: []
extra_info: []
assistant