code: def plot(m):
      plt.figure(figsize=(8, 4))
      Xtest = np.linspace(0, 1, 100)[:, None]
      (line,) = plt.plot(X1, Y1, "x", mew=2)
      mu, var = m.predict_f(np.hstack((Xtest, np.zeros_like(Xtest))))
      plot_gp(Xtest, mu, var, line.get_color(), "Y1")
  
      (line,) = plt.plot(X2, Y2, "x", mew=2)
      mu, var = m.predict_f(np.hstack((Xtest, np.ones_like(Xtest))))
      plot_gp(Xtest, mu, var, line.get_color(), "Y2")
  
      plt.legend()
  
imports: import matplotlib.pyplot
  import numpy
  import gpflow
  from gpflow.ci_utils import reduce_in_tests
label_desc: Use image node_id 2 for calling a global function with example usage: plot(m) without return types