How do I filter tasks by extended properties?

[Tre-Seibert]

I have this code which has several different extended properties. However, due to the shear amount of items in this folder, it takes forever to retrieve each and every item, with their respective extended property. How would one filter items based on extended properties to decrease runtime? In the following code I defined several extended properties. I want to filter the items in the tasks variable by the client name. So for an example I want to filter all the items by only retrieving items with the ".Client" extended property, and only if the extended property is equal to the string "BUCK". How would I achieve this?

    # Define extended property .Status
    class status(ExtendedProperty):
        distinguished_property_set_id = 'PublicStrings'
        property_name = '.Status'
        property_type = 'String'
    
    # Register the extended property on the task item type
    Task.register('status_property', status)

    # Define extended property .Client
    class client(ExtendedProperty):
        distinguished_property_set_id = 'PublicStrings'
        property_name = '.Client'
        property_type = 'String'
    
    # Register the extended property on the task item type
    Task.register('client_property', client)

    # Define extended property .Client
    class assignee(ExtendedProperty):
        distinguished_property_set_id = 'PublicStrings'
        property_name = '.Assignee'
        property_type = 'String'
    
    # Register the extended property on the task item type
    Task.register('assignee_property', assignee)

    # Define extended property .HrsBillableTotal
    class hrsbillabletotal(ExtendedProperty):
        distinguished_property_set_id = 'PublicStrings'
        property_name = '.HrsBillableTotal'
        property_type = 'Double'
    
    # Register the extended property on the task item type
    Task.register('hrsbillabletotal_property', hrsbillabletotal)

    # Define extended property .HrsBillableTotal
    class cause(ExtendedProperty):
        distinguished_property_set_id = 'PublicStrings'
        property_name = '.cause1'
        property_type = 'String'
    
    # Register the extended property on the task item type
    Task.register('cause_property', cause)

    # Define extended property .SystemTime
    class datelastactivity(ExtendedProperty):
        distinguished_property_set_id = 'PublicStrings'
        property_name = '.DateLastActivity'
        property_type = 'SystemTime'
    
    # Register the extended property on the task item type
    Task.register('datelastactivity_property', datelastactivity)

    # Fetch task items in the subfolder
    tasks = subfolder.all()

[ecederstrand]

When you have registered an extended property, you should be able to use it like any other field:

class SomeExtProp(ExtendedProperty):
    ...

Task.register('some_ext_prop', SomeExtProp)

for task in account.tasks.filter(some_ext_prop="something"):
    print(task.some_ext_prop)

[Tre-Seibert]

Thank you!