Find element in list of objects with explicit key value

Question

I have a list of objects in python:

accounts = [
    {
        'id': 1,
        'title': 'Example Account 1'
    },
    {
        'id': 2,
        'title': 'Gow to get this one?'
    },
    {
        'id': 3,
        'title': 'Example Account 3'
    },
]

I need to get object with id=2.

How can I select a proper object from this list, when I know only the value of the object attributes?

Answer 1

Given your data structure:

>>> [item for item in accounts if item.get('id')==2]
[{'title': 'Gow to get this one?', 'id': 2}]

If item does not exist:

>>> [item for item in accounts if item.get('id')==10]
[]

---

That being said, if you have opportunity to do so, you might rethink your datastucture:

accounts = {
    1: {
        'title': 'Example Account 1'
    },
    2: {
        'title': 'Gow to get this one?'
    },
    3: {
        'title': 'Example Account 3'
    }
}

You might then be able to access you data directly by indexing their id or using get() depending how you want to deal with non-existent keys.

>>> accounts[2]
{'title': 'Gow to get this one?'}

>>> accounts[10]
Traceback (most recent call last):
  File "<input>", line 1, in <module>
KeyError: 10

>>> accounts.get(2)
{'title': 'Gow to get this one?'}
>>> accounts.get(10)
# None

Answer 2

This will return any element from the list that has an id == 2

limited_list = [element for element in accounts if element['id'] == 2]
>>> limited_list
[{'id': 2, 'title': 'Gow to get this one?'}]

Answer 3

It seems to be a weird data structure, but it can be done:

acc = [account for account in accounts if account['id'] == 2][0]

Maybe a dictionary with the id-number as key is more appropriate, as this makes the accessing easier:

account_dict = {account['id']: account for account in accounts}