code: def _FirstNotNone(l):
      for x in l:
          if x is not None:
              return x
      return None
  
imports: import numpy
  from tensorboard.compat.proto import tensor_pb2
  from tensorboard.compat.tensorflow_stub import dtypes, compat, tensor_shape
label_desc: Use image node_id 20 for calling a global function with example usage: _FirstNotNone(l) and returns: None, x