Parse this person name:

Twan Korstman (1237-1279, flourished 1265-1274)
user
first_name: Twan
last_name: Korstman
middle_names: []
temporal:
- start: 1237
  end: 1279
  type: life_span
- start: 1265
  end: 1274
  type: flourished
titles: []
extra_info: []
assistant