class_docstr: Represents the output of a task. An output can be a blob,
  a list of blob, or a record.
class_docstr_tok: ["Represents","the","output","of","a","task",".","An","output","can","be","a","blob",",","a","list","of","blob",",","or","a","record","."]
code: def fetch(self):
      assert (
          self._fetch_func is not None
      ), "Cannot fetch value for this output."
      fetched_vals = [self._fetch_func(v) for v in self._values]
      if self._is_scalar:
          return fetched_vals[0]
      elif self._schema:
          return from_blob_list(self._schema, fetched_vals)
      else:
          return fetched_vals
  
imports: from caffe2.python import core, context
  from caffe2.python.schema import Field, from_blob_list
  from collections import defaultdict
  from copy import copy
label_desc: Use image node_id 4 for calling the TaskOutput obj's underlying member method code with example usage: obj.fetch() and returns: fetched_vals, from_blob_list, fetched_vals