What does "value" and "slot" refer to in this line of code in the Rasa Udemy Course?

I am enrolled in the Rasa Udemy Course, and in the part about custom actions, there is line of code at the end of an action:

return [SlotSet(slot, value) for slot, value in slots.items()]

I want to know what exactly is going on. Is it just resetting the values of all slots to None or something else? Also what does .items() do?

Thanks for the help!!

Hey @BrookieHub . slots is a dictionary if I remember correctly. So slots.items() is the method for python’s dictionaries that generates pairs of key,value. SlotSet(slot,value) is a method in Rasa actions to set the value value to the slot slot.

Thus, the whole expression is a list comprehession that will go through the key:value pairs of the dictionary slot (where “key”->slot and “value”->value) and for each pair will set the value of the slot to the corresponded value.

I hope it makes sense. :laughing:


Exactly what @EvanMath said. I would just like to add an example:

return [SlotSet(slot, value) for slot, value in slots.items()]

is the same as:

slots = {'slot1': 'value1', 'slot2': 'value2', ...}
slot_sets = []

for slot, value in slot.items(): # Translates to: for (slot, value) in [('slot1', 'value1'), ('slot2', 'value2'), ...]
    slot_sets.append(SlotSet(slot, value))

return slot_sets # Translates to: return [SlotSet('slot1', 'value1'), SlotSet('slot2', 'value2'), ...]