code: def subtract(a, b):
      """A version of tf.subtract that eagerly evaluates if possible."""
      return _maybe_static(a) - _maybe_static(b)
  
imports: import funcsigs
  import numpy
  import tensorflow.compat.v2
  from trax.tf_numpy.numpy_impl import arrays
  from trax.tf_numpy.numpy_impl import dtypes
label_desc: Use image node_id 21 for calling a global function with example usage: subtract(a, b) and returns: unknown