input: def is_adult(people, age_threshold):
      """ Given a list of dictionaries, where each dictionary represents a person with a 'name' and 'age' attribute, 
      return True if any of the people are older than or equal to the specified age_threshold, otherwise return False.
      >>> is_adult([{"name": "Alice", "age": 20}, {"name": "Bob", "age": 21}], 18)
      True
      >>> is_adult([{"name": "Charlie", "age": 17}, {"name": "David", "age": 15}], 18)
      False
      """
output:     for person in people:
          if person['age'] >= age_threshold:
              return True
      return False