code: def dot(x, y, sparse=False):
      """Wrapper for tf.matmul (sparse vs dense)."""
      if sparse:
          res = tf.sparse_tensor_dense_matmul(x, y)
      else:
          res = tf.matmul(x, y)
      return res
  
file_path: OpenNE/src/openne/gcn/layers.py
imports: from .inits import *
  import tensorflow
label_desc: Use image node_id 3 for calling a global function with example usage: dot(x, y, sparse) and returns: res