Sorting list of dictionaries in order of value of one of the keys in a dict
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`a=[{'post': 3, 'value': 42}, {'post': 4, 'value': 12}, {'post': 12, 'value': 25}]`

How can I sort it to this:


`a=[{'post': 3, 'value': 42}, {'post': 12, 'value': 25}, {'post': 4, 'value': 12}]`

I mean in order to value with reverse.