code: def rfft(x, fft_length=None):
      if fft_length is not None:
          fft_length = [fft_length]
      complex_output = tf.signal.rfft(x, fft_length=fft_length)
      return tf.math.real(complex_output), tf.math.imag(complex_output)
  
file_path: keras/keras/backend/tensorflow/math.py
imports: import tensorflow
  from keras.backend import standardize_dtype
  from keras.backend.tensorflow.core import convert_to_tensor
label_desc: Use image node_id 11 for calling a global function with example usage: rfft(x, fft_length) and returns: tf,  tf