Python: peculiar behavior when using json.load() / filter()

Question

My python is doing something super weird can I can't even start to understand what's going on.

I have a function like so:

def get_machine_config_by_id(machine_id):
    with open(Path("xxx.json"), "r") as f:
        machines = json.load(f)
        machine = filter(lambda x: x['id'] == machine_id, machines)
        return list(machine)[0]

which I call like so:

get_machine_config_by_id(m_id)['locator']

to get one of the properties of a machine (in this case locator).

Now the weirdness: it comes back as a tuple, even though it's stored as a string in xxx.json. In other words the above call results in

(value,)

But it gets weirder:

#this:
get_machine_config_by_id(m_id)['locator'][0]

#produces this:
(v,) #yes, another tuple, but now with just the first letter of the string...

#while this:
temp_store = get_machine_config_by_id(m_id)['locator']
actual = temp_store[0]

#produces this:
value #finally, the actual string

How on earth is this possible?

question from:https://stackoverflow.com/questions/65890091/python-peculiar-behavior-when-using-json-load-filter

Answer 1

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