code: def rsqrt(x):
      return 1.0 / np.sqrt(x)
  
imports: import numpy
  from keras.backend import standardize_dtype
  from keras.backend.jax.math import fft
  from keras.backend.jax.math import fft2
  from keras.backend.numpy.core import convert_to_tensor
  from keras.utils.module_utils import scipy
label_desc: Use image node_id 15 for calling a global function with example usage: rsqrt(x) and returns: unknown