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pythondictionarykeyunion

combining two dict_key instances with preserving their order

I have two dict with different keys. I would like to combine both keys into a list or something so that I can iterate over. However the order is important because at some places of the script I need to preserve the order for other calculations via enumerate()

Here is a small example of what I am trying to do:

ns.keys()
Out[1]: dict_keys([108])
no.keys()
Out[2]: dict_keys([120, 124, 126, 127, 112, 114, 115, 117, 118, 135, 132, 133, 109, 130, 111, 129, 136])

I want to iterate over both of them like following:

for key in [ns.keys() | no.keys()]:
    print(key)
Out[3]: {129, 130, 132, 133, 135, 136, 108, 109, 111, 112, 114, 115, 117, 118, 120, 124, 126, 127}

The order is important because, I also want to do following:

for i, key in enumerate([ns.keys() | no.keys()]):
    print(i, key)

I want the order of [ns.keys() | no.keys()] to be first ns.keys() then no.keys(). In this example, it should be:

[108, 120, 124, 126, 127, 112, 114, 115, 117, 118, 135, 132, 133, 109, 130, 111, 129, 136]

Following works list(ns.keys()) + list(no.keys()), any other idea?

Solution

  • Just unpack dict keys within a list for iteration:

    [*ns.keys(), *no.keys()]