code: def f(x, noise_level=noise_level):
      return (
          np.sin(5 * x[0]) * (1 - np.tanh(x[0] ** 2))
          + np.random.randn() * noise_level
      )
  
imports: import numpy
  import matplotlib.pyplot
  from skopt.plots import plot_gaussian_process
  from skopt import gp_minimize
  from skopt.plots import plot_convergence
label_desc: Use image node_id 1 for calling a global function with example usage: f(x, noise_level) and returns: unknown