Parse this person name:

Dex Opmans, 1241-1312, flourished 1259-1270
user
first_name: Dex
last_name: Opmans
middle_names: []
temporal:
- start: 1241
  end: 1312
  type: life_span
- start: 1259
  end: 1270
  type: flourished
titles: []
extra_info: []
assistant