Parse this person name:

Aleksej Hentschel (1240-1289, flourished 1261-1273)
user
first_name: Aleksej
last_name: Hentschel
middle_names: []
temporal:
- start: 1240
  end: 1289
  type: life_span
- start: 1261
  end: 1273
  type: flourished
titles: []
extra_info: []
assistant