code: def burr_pdf(x, cc, dd):
      # note: we use np.exp instead of math.exp, otherwise an overflow
      # error can occur in the setup, e.g., for parameters
      # 1.89128135, 0.30195177, see test test_burr_overflow
      if x > 0:
          lx = math.log(x)
          return np.exp(
              -(cc + 1) * lx - (dd + 1) * math.log1p(np.exp(-cc * lx))
          )
      else:
          return 0
  
imports: import math
  import numbers
  import numpy
  from scipy import stats
  from scipy import special
  from ._qmc import check_random_state, Halton, QMCEngine
  from ._unuran.unuran_wrapper import NumericalInversePolynomial
  from scipy._lib._util import check_random_state
label_desc: Use image node_id 8 for calling a global function with example usage: burr_pdf(x, cc, dd) and returns: np, int