docstr: Insert input of this op
  also maintain the output of previous op
  p: a node or a list of node
docstr_tok: ["Insert","input","of","this","op","also","maintain","the","output","of","previous","op","p",":","a","node","or","a","list","of","node"]
code: def insertInput(self, p):
      """
      Insert input of this op
      also maintain the output of previous op
      p: a node or a list of node
      """
      if isinstance(p, list):
          for i in p:
              self.prev[i.name] = i
              i.ops[self.name] = self
      elif isinstance(p, NetDefNode):
          self.prev[p.name] = p
          p.ops[self.name] = self
  
file_path: pytorch/caffe2/experiments/python/SparseTransformer.py
imports: from caffe2.python import workspace
  import scipy.sparse
label_desc: Use image node_id 2 for calling the NetDefNode obj's underlying member method code with example usage: obj.insertInput(p) without return types