python - compare two list of dictionaries and update list with missing key value pair

Question

I have two list dictionaries'

L1 =  [{'y': 3L, 'x': u'2016-10'}, {'y': 3L, 'x': u'2016-12'}]
L2 = [{'y': 0, 'x': '2016-12'}, {'y': 0, 'x': '2016-11'}, {'y': 0, 'x': '2016-10'}]

Compare these two list with value of x.

Final out put like:

output= [{'y': 3L, 'x': '2016-12'}, {'y': 0, 'x': '2016-11'}, {'y': 3L, 'x': '2016-10'}]

How can i do it?

Answer 1

Enjoy:

L1 =  [{'y': 3L, 'x': u'2016-10'}, {'y': 3L, 'x': u'2016-12'}]
L2 = [{'y': 0, 'x': '2016-12'}, {'y': 0, 'x': '2016-11'}, {'y': 0, 'x': '2016-10'}]

output = []
for e2 in L2:
    found = False
    for e1 in L1:
        if e1['x'] == e2['x']:
            output.append(e1)
            found = True
            break
    if not found:
        output.append(e2)

print output # output= [{'y': 3L, 'x': '2016-12'}, {'y': 0, 'x': '2016-11'}, {'y': 3L, 'x': '2016-10'}]