如何将字典列表转换为字典？

Question

I have a list of dict that I am struggling to change to list of dicts:

x = [
    { # begin first and only dict in list
        '11': [{'bb': '224', 'cc': '14'}, {'bb': '254', 'cc': '16'}]
        , '22': [{'bb': '824', 'cc': '19'}]
    }
]

Which currently has a length of 1. ie:

print(len(x)) # 1

I intend to change it to list of dicts. ie:

desired = [
    { # begin first dict in list
        '11': [{'bb': '224', 'cc': '14'}, {'bb': '254', 'cc': '16'}]
    }
    , { # begin second dict in list
        '22': [{'bb': '824', 'cc': '19'}]
    }
]
    
print(len(desired)) # 2

What I tried:

dd = {}
for elem in x:
    for k,v in elem.items():
        dd[k] = v
print([dd])

print(len(dd)) # 2

Is there a better way or perhaps more efficient way?

Answer 1

Like others mentioned, there is nothing "wrong" with what you've tried. However, you might be interested in trying a list comprehension:

x_desired = [{k: v} for i in x for k, v in i.items()]

Like your attempted approach, this is effectively 2 for loops, the second nested within the first. In general, list comprehensions are considered fast and Pythonic.

Answer 2

Do you want the result to be 2 as you"ve got two keys ( 11 & 22 )? then try this:

print(len(x[0]))