通过for循环修改OrderedDict的列表

Question

I am trying to loop over a list of OrderedDict and redefine these OrderedDict elements.

To illustrate, consider the list:

dict_list = [
    OrderedDict([("key1",1)]),
    OrderedDict([("key1",2)])
]

I want to add a new key "key2" on all the dicts.

for var in dict_list:
     var["key2"] = 1

But that will add this key at the end of the OrderedDict, while I want to add it at the beginning, so I try this:

for var in dict_list:
     var = OrderedDict([("key2",1)] + list(var.items()))

The change is no remembered outside the for loop (maybe because I am trying to redefine the iterator?)

Answer 1

You can do:

var["key2"] = 1
var.move_to_end("key2", last=False)