code: def data_fun(times, latency, duration):
      """Generate source time courses for evoked responses."""
      f = 15  # oscillating frequency, beta band [Hz]
      sigma = 0.375 * duration
      sinusoid = np.sin(2 * np.pi * f * (times - latency))
      gf = np.exp(
          -((times - latency - (sigma / 4.0) * rng.rand(1)) ** 2)
          / (2 * (sigma**2))
      )
      return 1e-9 * sinusoid * gf
  
imports: import numpy
  import mne
  from mne.datasets import sample
label_desc: Use image node_id 1 for calling a global function with example usage: data_fun(times, latency, duration) and returns: unknown