Parse this person name:

Merle van Rossum, 1207-1251, flourished 1233-1246
user
first_name: Merle
last_name: van Rossum
middle_names: []
temporal:
- start: 1207
  end: 1251
  type: life_span
- start: 1233
  end: 1246
  type: flourished
titles: []
extra_info: []
assistant