code: def basis(self, x, knot, min_knot, max_knot):
      lambda_ = (max_knot - knot) / (max_knot - min_knot)
      return self.relu(x - knot) ** 3 - (
          lambda_ * self.relu(x - min_knot) ** 3
          + (1 - lambda_) * self.relu(x - max_knot) ** 3
      )
  
imports: from autograd import numpy
  from lifelines.datasets import load_lymph_node
  from lifelines.fitters import ParametricRegressionFitter
  from autograd.scipy.special import expit
  import pandas
  from lifelines import CoxPHFitter
  from matplotlib import pyplot
label_desc: Use image node_id 2 for calling the SplineFitter obj's underlying member method code with example usage: obj.basis(x, knot, min_knot, max_knot) and returns: unknown