input: Write a python function to create a tree from a list of dictionaries with 'age' and 'name' keys.
  assert create_tree([{'age': 30, 'name': 'Alice'}, {'age': 25, 'name': 'Bob'}]) == {
      'age': None,
      'children': [
          {'age': 30, 'name': 'Alice', 'children': []},
          {'age': 25, 'name': 'Bob', 'children': []}
      ]
  }
  assert create_tree([{'age': 50, 'name': 'Eve'}]) == {
      'age': None,
      'children': [
          {'age': 50, 'name': 'Eve', 'children': []}
      ]
  }
  assert create_tree([]) == {
      'age': None,
      'children': []
  }
output: def create_tree(person_list):
      tree = {'age': None, 'children': []}
      for person in person_list:
          person_with_children = {**person, 'children': []}
          tree['children'].append(person_with_children)
      return tree