Parse this person name:

Youssef Walsteijn, 1815-1857, flourished 1844-1852
user
first_name: Youssef
last_name: Walsteijn
middle_names: []
temporal:
- start: 1815
  end: 1857
  type: life_span
- start: 1844
  end: 1852
  type: flourished
titles: []
extra_info: []
assistant