Python filter specific item using one line of code-CodePudding

From this code snippet...

myItem = {
    'A/A': {'id': 'AA','bool': False},
    'A/B': {'id': 'AB','bool': True},
    'A/C': {'id': 'AC','bool': False},
    'A/D': {'id': 'AC','bool': True}
}

how do I filter myItem so that I only get those item that has 'bool': True in it?

I tried doing list comprehension to get ['A/B'] like so:

[item for item in myItem if item.endswith('B')]

I tried...

[item for item in myItem if item.bool==True]

but it's giving me an error:

AttributeError: 'str' object has no attribute 'bool'

All I want is to get items ['A/B', 'A/D'] by filtering 'bool': True, but unfortunately, I don't know how to do it.

CodePudding user response：

You can reconstruct the dictionary object with comprehension, like this

myItem = {
    'A/A': {'id': 'AA', 'bool': False},
    'A/B': {'id': 'AB', 'bool': True},
    'A/C': {'id': 'AC', 'bool': False},
    'A/D': {'id': 'AC', 'bool': True}
}

print({key: value for key, value in myItem.items() if value.get('bool', False)})

might print

{
    'A/B': {'bool': True, 'id': 'AB'},
    'A/D': {'bool': True, 'id': 'AC'}
}

The key here is to iterate through all the key-value pairs of myItem and filter the items based on the value dictionary's bool key.

if value.get('bool', False) is to ensure that if bool is not found in the dictionary, we ignore that. So, if bool is not present, then by default False would be returned.

CodePudding user response：

You can use filter to filter only items meeting a specific condition and then create a new dictionary out of them (or a list if you prefer):

dict(filter(lambda x: x[1].get('bool'), myItem.items()))

This is the result:

{'A/B': {'id': 'AB', 'bool': True}, 'A/D': {'id': 'AC', 'bool': True}}