Question

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how to uniqify a list of dict in python

I have a list as follows

[
{'x':'1','y':'1'},{'x':'2','y':'2'},{'x':'1','y':'1'}
]

I want to get a new list as follows (unique elements)

[
{'x':'1','y':'1'},{'x':'2','y':'2'}
]

What’s the best way?

Answer 1

import ast

l = [
{'x':'1','y':'1'},{'x':'2','y':'2'},{'x':'1','y':'1'}
]

[ast.literal_eval(el1) for el1 in set([str(el2) for el2 in l])]

Usually an easy solution for keeping unique elements is to add them to a set. However, since a dict is unhashable (can’t be put in a set), I provided a workaround. First, the dicts are converted to strings, placed in a set (to keep the unique ones), and then converted back to dicts using ast.literal_eval.