class_docstr: Tests of GraphAttention layer
class_docstr_tok: ["Tests","of","GraphAttention","layer"]
code: def get_matrix(self, edges=[]):
      # adjacency matrix with self-loops only
      A = np.eye(self.N)
      for e, v in edges:
          A[e[0], e[1]] = v
      return [A[None, :, :]]
  
imports: import pytest
  import scipy.sparse
  import tensorflow
  from tensorflow import keras
  from tensorflow.keras import backend
  from tensorflow.keras.layers import Input
  from stellargraph.mapper import FullBatchNodeGenerator, FullBatchLinkGenerator, GraphSAGENodeGenerator
  from stellargraph.layer import *
  from ..test_utils.graphs import example_graph
  from ..None import test_utils
label_desc: Use image node_id 2 for calling the Test_GraphAttention obj's underlying member method code with example usage: obj.get_matrix(edges) and returns: list