code: def myagg(alist, dsttype):
      rst = alist[0]
      for i in range(1, len(alist)):
          rst = rst + (i + 1) * alist[i]
      return rst
  
imports: from copy import deepcopy
  import backend
  import dgl
  import dgl.function
  import dgl.nn.tensorflow
  import networkx
  import numpy
  import pytest
  import scipy
  import tensorflow
  from tensorflow.keras import layers
  from utils import parametrize_idtype
  from utils.graph_cases import get_cases, random_bipartite, random_dglgraph, random_graph
label_desc: Use image node_id 19 for calling a global function with example usage: myagg(alist, dsttype) and returns: rst