code: def is_tensor(*, x):
      return isinstance(x, (tf.IndexedSlices, tf.Tensor, tf.Variable))
  
file_path: tensorforce/tensorforce/core/utils/tf_util.py
imports: import tensorflow
  from tensorforce import TensorforceError
label_desc: Use image node_id 1 for calling a global function with example usage: is_tensor() and returns: isinstance