code: def _check_pickle(op):
      """Check that an operation can be dumped and reloaded with pickle."""
      pickled = pickle.dumps(op)
      unpickled = pickle.loads(pickled)
      assert (
          unpickled == op
      ), "operation must be able to be pickled and unpickled"
  
file_path: pennylane/pennylane/ops/functions/assert_valid.py
imports: from string import ascii_lowercase
  import copy
  import pickle
  import numpy
  import pennylane
  from pennylane.operation import EigvalsUndefinedError
label_desc: Use image node_id 8 for calling a global function with example usage: _check_pickle(op) without return types