input: Write a python function to merge a list of dictionaries.
  assert merge_dicts([{'a': 1, 'b': 2}, {'b': 3, 'c': 4}]) == {'a': 1, 'b': 3, 'c': 4}
  assert merge_dicts([{'x': 9}, {'y': 8}, {'z': 7}]) == {'x': 9, 'y': 8, 'z': 7}
  assert merge_dicts([{'k1': 'v1'}, {'k2': 'v2'}, {'k1': 'v3'}]) == {'k1': 'v3', 'k2': 'v2'}
output: def merge_dicts(dict_list):
      merged_dict = {}
      for d in dict_list:
          merged_dict.update(d)
      return merged_dict