I have a data structure with collections and subcollections. Like below:

- Parent Collection 
   * Child document 1
       - Sub collection
           * Sub document 1
           * Sub document 2
              ...
           * Sub document n   
   * Child document 2
       - Sub collection
           * Sub document 1
           * Sub document 2
              ...
           * Sub document n   

How can I create a query using Python to get all documents from the parent collection but only with the first two sub-documents from the sub-collection of each child document?