input: Write a python function to find the best solution using a greedy algorithm.
  assert greedy_algorithm([{'value': 10}, {'value': 20}, {'value': 15}]) == {'value': 20}
  assert greedy_algorithm([{'value': 5}, {'value': 3}, {'value': 8}, {'value': 2}]) == {'value': 8}
  assert greedy_algorithm([{'value': -1}, {'value': -5}, {'value': -3}]) == {'value': -1}
output: def greedy_algorithm(items):
      best_solution = max(items, key=lambda x: x['value'])
      return best_solution