Parse this person name:

Guus Ernst (1254-1305, flourished 1274-1300)
user
first_name: Guus
last_name: Ernst
middle_names: []
temporal:
- start: 1254
  end: 1305
  type: life_span
- start: 1274
  end: 1300
  type: flourished
titles: []
extra_info: []
assistant