code: def get(self, *args, **kwargs):
          
          for collection in self.items:
              if args:
                  index = args[0]
                  if len(collection) and (index <= len(collection)-1):
                      return collection[index]
              else:
                  # Collection with get
                  result = collection.get(**kwargs)
                  if result is not None:
                      return result
          return None
docs: Get from the interface collection. It is more accurate to use
          kwargs to specify an attribute of the sub interface to retrieve
          rather than using an index value. If retrieving using an index,
          the collection will first check vlan interfaces and standard
          interfaces second. In most cases, if VLANs exist, standard
          interface definitions will be nested below the VLAN with exception
          of Inline Interfaces which may have both.
          
          :param int args: index to retrieve
          :param kwargs: key value for sub interface
          :rtype: SubInterface or None