Parse this person name:

Gunnar Briemer (1220-1266, flourished 1249-1261)
user
first_name: Gunnar
last_name: Briemer
middle_names: []
temporal:
- start: 1220
  end: 1266
  type: life_span
- start: 1249
  end: 1261
  type: flourished
titles: []
extra_info: []
assistant