Python: create a list of dictionaries using a list comprehension

I have a list of dictionaries, and I want to use it to create another list of dictionaries, slightly amended.

Here's what I want to do:

entries_expanded[:] = [{entry['id'], myfunction(entry['supplier'])} for entry in entries_expanded]

So I end up with another list of dictionaries, just with one entry altered.

The syntax above is broken. How can I do what I want?

Please let me know if I should expand the code example. 开发者_如何学C

To create a new dictionary for each, you need to restate the keys:

entries_expanded[:] = [{'id':entry['id'], 'supplier':myfunction(entry['supplier'])} for entry in entries_expanded]

(If I've understood what you're trying to do correctly, anyway)

Isn't this what you want?

entries_expanded[:] = [
    dict((entry['id'], myfunction(entry['supplier']))) 
    for entry in entries_expanded
]

You could think of it as a generator that creates tuples followed by a list comprehension that makes dictionaries:

entryiter = ((entry['id'], entry['supplier']) for entry in entries_expanded)
tupleiter = ((id, myfunction(supplier)) for id, supplier in entryiter)
entries_expanded[:] = [dict(t) for t in tupleiter]

Alternatively, it is as the other answer suggests:

entryiter = ((entry['id'], entry['supplier']) for entry in entries_expanded)
tupleiter = ((id, myfunction(supplier)) for id, supplier in entryiter)
entries_expanded[:] = [
    dict((('id', id), ('supplier', supplier))) 
    for id, supplier in tupleiter
]