code: def rank(self):
      return len(self.shape)
  
imports: from functools import total_ordering
  import numpy
  import tensorflow
  from tensorforce import TensorforceError, util
  from tensorforce.core.utils import tf_util
label_desc: Use image node_id 3 for calling the TensorSpec obj's underlying member method code with example usage: obj.rank() and returns: len