Parse this person name:

Leni Köster (1753-1798, flourished 1781-1793)
user
first_name: Leni
last_name: Köster
middle_names: []
temporal:
- start: 1753
  end: 1798
  type: life_span
- start: 1781
  end: 1793
  type: flourished
titles: []
extra_info: []
assistant