class_docstr: Spatial Temporal Embedding
  
  Apply GAT and Conv1D based on Temporal and Spatial Correlation
code: def _reduce_attention(self, msg):
      alpha = msg.reduce_softmax(msg["alpha"])
      return msg.reduce(msg["output_series"] * alpha, pool_type="sum")
  
imports: import pgl
  import paddle
  import paddle.nn
  import paddle.nn.functional
  import numpy
  from pgl.utils.logger import log
  import pgl.nn
  import math
label_desc: Use image node_id 3 for calling the SpatialTemporalConv obj's underlying member method code with example usage: obj._reduce_attention(msg) and returns: msg