How to set attributes of copied special layer in script?

Scripting
1

Hello, I would like to duplicate some special layers and change their coordinate attributes.

I tried this:

for l in [l for l in Layer.parent.layers]:
	if l.isSpecialLayer and not l.isMasterLayer:
		if l.attributes["coordinates"]["a01"] == 34:
			copy_layer = l.copy()
			l.parent.layers.append(copy_layer)
			copy_layer.attributes["coordinates"]["a01"] = 85

However, I get:

Traceback (most recent call last):
  File "<macro panel>", line 6
TypeError: '__NSFrozenDictionaryM' object does not support item assignment

How can I achieve what I am looking to do? Thanks!

2 
for l in [l for l in Layer.parent.layers]:
	if l.isSpecialLayer and not l.isMasterLayer:
		if l.attributes["coordinates"]["a01"] == 34:
			copy_layer = l.copy()
			l.parent.layers.append(copy_layer)
			coordinates = dict(copy_layer.attributes["coordinates"])
			coordinates["a01"] = 85
			copy_layer.attributes["coordinates"] = coordinates
3

Thank you very much!