Parse this person name:

Sigmund Köster, 1319-1376, flourished 1348-1358
user
first_name: Sigmund
last_name: Köster
middle_names: []
temporal:
- start: 1319
  end: 1376
  type: life_span
- start: 1348
  end: 1358
  type: flourished
titles: []
extra_info: []
assistant