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Jesus_jbs
Asked: 2022-06-16 03:53:50 +0800 CST 2022-06-16 03:53:50 +0800 CST

Flatten list and convert string to set

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I have the following list:

result = [{"{'rueda-pinchada', 'rueda-repuesto'}", " {'eje', 'maletero', 'suelo'}"}]

and I want to get the following:

result = [{'rueda-repuesto', 'rueda-pinchada'}, {'maletero', 'eje', 'suelo'}]

As you can see, the second list contains two sets, while the first contains a set with two strings that "mimic" a set. The idea is to flatten the list to get the two strings, and with the list of strings, convert these to set. Remaining a list of sets.

I have tried to flatten it as follows:

aux = [constante for x in result for constante in x]

and has resulted in:

['{', "'", 'r', 'u', 'e', 'd', 'a', '-', 'p', 'i', 'n', 'c', 'h', 'a', 'd', 'a', "'", ',', ' ', "'", 'r', 'u', 'e', 'd', 'a', '-', 'r', 'e', 'p', 'u', 'e', 's', 't', 'o', "'", '}', ' ', '{', "'", 'e', 'j', 'e', "'", ',', ' ', "'", 'm', 'a', 'l', 'e', 't', 'e', 'r', 'o', "'", ',', ' ', "'", 's', 'u', 'e', 'l', 'o', "'", '}']
python

1 Answers

  1. Best Answer

    We have to untangle the initial expression a bit:

    result = [{"{'rueda-pinchada', 'rueda-repuesto'}", " {'eje', 'maletero', 'suelo'}"}]

    resultit is a list. This list contains a set with two elements of type string :

    • {'flat-wheel', 'spare-wheel'}
    • {'axle', 'trunk', 'floor'}

    The content of each string is the text representation of a set .

    The function evalcan take a python code, execute it and return the result produced. In this case, the code is simply defining a set .

    So if we run:

    eval("{'eje', 'maletero', 'suelo'}")

    it will be seen that the argument (as string ) creates a set. evalwill return that set.

    Code

    Using list comprehension, we loop through the set evaluating its elements and appending them to the final list

    nuevo = [eval(item) for item in result[0]]

    show

    print(nuevo)

    produces:

    [{'rueda-repuesto', 'rueda-pinchada'}, {'maletero', 'eje', 'suelo'}]
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